AQA Combined Science, Trilogy (8464)CHEMISTRY

-Atomic Structure and the Periodic Table (Paper 1 – Topic 1)

- Chemical Analysis (Paper 2 – Topic 8)

-Structure and Bonding (Paper 1 – Topic 2)

-Organic Chemistry (Paper 2 – Topic 7)

-Chemistry of the Atmosphere (Paper 2 – Topic 9)

NAME ____________________________________

CLASS ____________________________________

TEACHER ____________________________________

Personalised Learning Checklist 1

AQA Chemistry (9-1) Paper 1 – Topic 1 Atomic structure and the periodic tableTopic Student Checklist R A G

4.1.

1 A

sim

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mod

el o

f the

ato

m, s

ymbo

ls, re

lativ

e at

omic

mas

s, e

lect

roni

c cha

rge

and

isoto

pes

State that everything is made of atoms and recall what they are Describe what elements and compounds are State that elements and compounds are represented by symbols; and use chemical symbols and formulae to represent elements and compounds

Write word equations and balanced symbol equations for chemical reactions, including using appropriate state symbols

HT ONLY: Write balanced half equations and ionic equations

Describe what a mixture is

Name and describe the physical processes used to separate mixtures and suggest suitable separation techniques

Describe how the atomic model has changed over time due to new experimental evidence, inc discovery of the atom and scattering experiments (inc the work of James Chadwick)

Describe the difference between the plum pudding model of the atom and the nuclear model of the atom

State the relative charge of protons, neutrons and electrons and describe the overall charge of an atom

State the relative masses of protons, neutrons and electrons and describe the distribution of mass in an atom

Calculate the number of protons, neutrons and electrons in an atom when given its atomic number and mass number

Describe isotopes as atoms of the same element with different numbers of neutrons

Define the term relative atomic mass and why it takes into account the abundance of isotopes of the element

Calculate the relative atomic mass of an element given the percentage abundance of its isotopes

Describe how electrons fill energy levels in atoms, and represent the electron structure of elements using diagrams and numbers

4.1.

2 T

he p

erio

dic t

able

Recall how the elements in the periodic table are arranged Describe how elements with similar properties are placed in the periodic table Explain why elements in the same group have similar properties and how to use the periodic table to predict the reactivity of elements

Describe the early attempts to classify elements Explain the creation and attributes of Mendeleev's periodic table Identify metals and non-metals on the periodic table, compare and contrast their properties

Explain how the atomic structure of metals and non-metals relates to their position in the periodic table

Describe nobel gases (group 0) and explain their lack of reactivity Describe the properties of noble gases, including boiling points, predict trends down the group and describe how their properties depend on the outer shell of electrons

Describe the reactivity and properties of group 1 alkali metals with reference to their electron arrangement and predict their reactions

Describe the properties of group 7 halogens and how their properties relate to their electron arrangement, including trends in molecular mass, melting and boiling points and reactivity

Describe the reactions of group 7 halogens with metals and non-metals

Chem ONLY: Describe the properties of transition metals and compare them with group 1 elements, including melting points and densities, strength and hardness, and reactivity (for CR, Mn Fe, Co, Ni & Cu)

Just Learn Facts – These are facts that you need to learnProcesses – Make sure you can complete all of

these tasks

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Elements are made up of only one types of atom Mixture are 2 or more elements not chemically joined together Compounds are 2 or more elements chemically joined together

People believed that the atom was the smallest undividable object The discovery of the electron led to the plum pudding model Rutherford and Marsden’s experiments led to the nuclear model Niels Bohr adapted the nuclear model by suggesting electrons orbit the nucleus at specific

distances

Atoms have a nucleus in the middle made of protons and neutrons and electrons in shells around the nucleus

In an atom the number of protons is equal to the number of electrons The atomic number of an element is the number of protons The mass number is the number of protons and neutrons An isotope is a different form of an element with the same number of protons and electrons but

a different number of neutrons

Electrons fill up from the inside shell first Elements in the same group have the same number of electrons in their outer shell giving them

similar chemical properties

Newlands and Mendeleev attempted to arrange the elements in order of atomic weight Mendeleev arranged elements in groups with similar properties Mendeleev noticed that some elements were put in the wrong groups if the order of atomic

weight was strictly used. Mendeleev left gaps in the periodic table for elements to be discovered

In the modern periodic table the elements are arranged in order of atomic number Metals are on the left of the periodic table and non-metals are on the right Groups contain elements with similar properties The group the element is in represents the number of electrons in the outer shell The row the elements are in represents the number of shells the atom has

The elements in group 8/0 are called noble gases. They have a full outer shell and so don’t react

The elements in group 1 are known as the alkali metals1. The metals are low density2. They react to form ionic compounds with a +1 charge3. They react with water releasing hydrogen4. They form hydroxides that dissolve in water

As you go down group 1 the metals get more reactive and have a lower melting and boiling point

Group 7 non-metals are known as halogens and react to form ionic compounds with -1 ions As you go down group 7 the elements get less reactive and have higher melting and boiling points A more reactive halogen can displace a less reactive halogen

Describe different methods of separating mixtures using filtration, crystallisation, distillation, fractional distillation and chromatography

Explain the difference between the plum pudding model and the nuclear model of the atom

Describe the relative charges and relative mass of protons, neutrons and electrons

Draw the electronic structure of elements 1-20

Describe the steps involved in the development of the periodic table

Identify the metals and non-metals in the periodic table

Explain why the reactivity of the group 1 elements changes as you go down the group

Explain why the reactivity of the group 7 elements changes as you go down the group

Write word and symbol equations for the group 7

displacement reactions

L1 – Elements, mixtures and compounds

All: State the definition of elements, mixtures and compounds Most: Understand that elements are represented by symbols

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Some: Explain different techniques for separating mixtures

Write down the definitions of the Keywords

Element

Mixture

Compound

Complete the gaps in the following passage using the elements names or symbols from the periodic table.

The burglar had been caught red-handed with the (Ag) __________ and (Au) ___________. He had been caught after a high speed (carbon + argon) ___________ chase.

The inspector was anxious to get this one (Fe) ______ed out before the end of the night. The victim arrived at the station shouting (holmium + tungsten) __________ dare someone (sulphur + tellurium + aluminium)

_________ from me.The (cobalt) _____nstable (potassium + neon + tungsten) ___________ this was not going to be an easy

(calcium + selenium) ____________ to solve.

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Draw a flow map explaining how Filtration works?(use key terminology)

Draw a flow map explaining how Filtration works?(use key terminology)

Draw a flow map explaining how Distillation works?(use key terminology)

Explain how you would separate a mixture of salt, sand and water so that you can keep all 3 substances?

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Separating Rock Salt ExperimentLabel the diagram and then fill in the missing words in the text below (the words are provided for you)

Distillate condenser thermometer solution

Distillation works when the solution is heated up and ____________. Only the _________________ evaporates,

the ______________ is left behind in the flask.

Evaporated __________ ___________ is cooled in the _______________ and turn into little ethanol

______________.

Evaporates droplets water ethanol

condenser ethanol vapour

Crush the rock salt in a pestle and mortar

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Add the rock salt to 50 ml of water and stir with a glass rod Filter the mixture into a beaker to remove the sand Put the mixture in a evaporating dish Evaporate the water to leave the salt

Method Evaluation

What are the good things about the method we used?

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What were the limitations of our method?

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L2 – History of the atom

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All Describe how the atomic model developed over time Most Explain the difference between the plum pudding model and the nuclear model

Some Describe all features of the modern atomic model

Starter:Complete the bubble map with any words that describe the atom

Atomic Structure Video Quiz

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The Atom

1. What did Thompson discover?

2. In his experiment what did he change and what did he

measure?

3. What model of the atom did he make? Draw a diagram to

explain.

4. What did Rutherford discover?

5. In his experiment what did he bombard at the gold foil?

6. How was his model of the atom different to Thompson’s?

7. If an apple is the nucleus – How far away is an electron?

8. Later on, what did he discover in the nucleus?

Draw diagrams for both the plum pudding models

Label all sub-atomic particles and identify their relative mass and charge

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Plum pudding Model Nuclear Model

Draw a double bubble map comparing the Plum Pudding and Nuclear Atomic Models

L3 – Electronic Configuration

All Define mass number and atomic number

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Most Calculate the number of each type of sub-atomic particle for a named atomSome Draw the electronic structure of elements 1-20

Starter: Draw an atom – what would it look like?What information can you use to help you?

Complete the following table for each subatomic particle, showing their Relative Mass, Charge and position in the atom.

Subatomic Particle Relative Mass Relative Charge Position in the Atom

Proton

Neutron

Electron

What does the Periodic Table tell you about Atomic Structure?

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How many Protons, Neutrons and Electrons are in the following atoms?

Protons - Protons - Protons - Protons - Protons -

Neutrons - Neutrons - Neutrons - Neutrons - Neutrons -

Electrons - Electrons - Electrons - Electrons - Electrons -

True or False

1. The number of protons is always the same as the number of neutrons in the nucleus.

2. Most of the atom is empty space.

3. Most of the mass of the atom is in the nucleus.

4. The electron is the heaviest sub – atomic particle.

5. The mass number is the total number of neutrons and protons in the nucleus.

Complete the electronic structure of elements 1-20

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Exam Questions

Q1. Rock salt is a mixture of sand and salt.

Salt dissolves in water. Sand does not dissolve in water.

Some students separated rock salt.

This is the method used.13

1.      Place the rock salt in a beaker.2.      Add 100 cm3 of cold water.3.      Allow the sand to settle to the bottom of the beaker.4.      Carefully pour the salty water into an evaporating dish.5.      Heat the contents of the evaporating dish with a Bunsen burner until salt crystals start to form.

(a)     Suggest one improvement to step 2 to make sure all the salt is dissolved in the water.

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(b)     The salty water in step 4 still contained very small grains of sand.

Suggest one improvement to step 4 to remove all the sand.

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(c)     Suggest one safety precaution the students should take in step 5.

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(d)     Another student removed water from salty water using the apparatus in the figure below.

 

Describe how this technique works by referring to the processes at A and B.

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(e)     What is the reading on the thermometer during this process?

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        __________________ °C(1)

(Total 6 marks)

Q2.Magnesium burns in oxygen.

(a)     Use the Chemistry Data Sheet to help you to answer this question.

The word equation for magnesium burning is:

magnesium   +   oxygen        magnesium oxide

Draw one line from each substance to its correct description. 

Substance   Description

    compound

magnesium    

    metal

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magnesium oxide    

    mixture

oxygen    

    non-metal

(3)

(b)     The diagram represents a magnesium atom.

 

Complete the table to show the name of each particle and the charge of each particle in the magnesium atom.

 

Name of particle Charge

proton +1

neutron ______

____________ _____ −1

(2)

(c)     Use the Chemistry Data Sheet to help you to answer these questions.

Draw a ring around the correct answer to complete each sentence.

 

(i)

  core.

In a magnesium atom, the protons and neutrons are in the nucleus.

  shell.16

(1)

 

(ii)

  atomic number

The number of protons in a magnesium atom is the mass number.

  group number.

(1)

 

(iii)

  atomic number.

The sum of the protons and neutrons in a magnesium atom is the mass number.

  group number.

(1)(Total 8 marks)

Q3.There are eight elements in the second row (lithium to neon) of the periodic table.

(a)     Figure 1 shows an atom with two energy levels (shells).

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(i)      Complete Figure 1 to show the electronic structure of a boron atom.(1)

(ii)     What does the central part labelled Z represent in Figure 1?

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(iii)    Name the sub-atomic particles in part Z of a boron atom.

Give the relative charges of these sub-atomic particles.

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(b)     The electronic structure of a neon atom shown in Figure 2 is not correct.

 

Explain what is wrong with the electronic structure shown in Figure 2.

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(Total 8 marks)

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L4 – The Periodic Table

All Describe the features of the periodic tableMost Explain how the position of an element in the periodic table links to its electronic structure

Some Be able to use the periodic table to predict the formula of ions

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What did you learn from the element sort activity about how elements are sorted in the periodic table?

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On your periodic table:

1. Show clearly the staircase that separates the metals and non-metals.2. Colour the metals and on metals in different colours.

Summary

5 Elements that are solid at Room

Temperature

4 Elements that are non-metals

3 Metals that are used in Jewellery

2 Gas Elements that are found in our atmosphere

1 Metal that is liquid at Room

Temperature

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Further Patterns in the periodic tableWhat information do the Groups and Periods tell you about the structure of the atom

Group Number

Period Number

What is the link between the Group number and the charge of the ion formed?

Why do you think this is?

Element symbol Metal/Non-Metal Group Number Ion

Sodium Na Metal 1 Na1+

Magnesium Mg Metal 2 Mg2+

Oxygen O Non-Metal 6 O2-

Chlorine Cl Non-Metal 7 Cl1-

What is the link between the group number and the charge on the ion formed?

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How can the group number help predict the formula of simple ions?

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L5 – The Periodic Table History

All Explain how the modern periodic table is arrangedMost Evaluate the work of Newlands and Mendeleev in terms of their contribution to the periodic table

Some Explain the properties and trends in Group 0

True or False

The periodic table is the only way to classify the elements

Most elements are metals

Most metals are gases at room temperature

The periodic table can be used to make predictions about the products formed in reactions

Most non-metallic elements are gases at 20°C

The metals are on the right of the periodic table

Element Card Sort

How did you order the elements?

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How did your choice make it easy to identify the elements?

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What are the limitations for your chosen organisation of the elements?

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Why is the periodic table important?

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Flow Map Make a flow diagram showing the development of the periodic table

Focus on the work done by Mendeleev Explain what the modern periodic table tells us about the elements

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L6 – Group 1

All Describe the physical and chemical properties of the group 1 metalsMost Explain the trends in reactivity of the group 1 metals

Some Write symbol equations for the reactions of group 1 metals and water

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Watch the demonstration and Complete the results table below

Element Symbol Observations Word Equation

Lithium

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Group 1

Alkali Metals

Prior Knowledge

Sodium

Potassium

Group 1 ReactivityComplete the electronic configuration for the first three elements in group 1 and write and explanation for the

pattern of reactivity in terms of their atomic structure

Electronic Configuration Reactivity Explanation

Exam Questions

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L7 – Group 7 (The Halogens)

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All Describe the physical and chemical properties of the group 7 halogensMost Explain the trends in reactivity of the halogens

Some Explain halogen displacement reactions

Which words are the statements describing? The other name of group 7 elements A 1- ion made from halogens A reaction where a more reactive element takes the place of a less reactive element in its compound Halogens exist as ‘2-atom’ molecules, another name for this

Atomic Number Element Formula Colour and

State

Melting Point

°C

Boiling Point

°C

ElectronConfiguratio

n

Fluorine Pale yellow gas -220 -188

17

35 Br2 Ends in .7

Iodine Ends in .7

85 Black solid 302 337 Ends in .7

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Investigating the reactivity of the halogens

Aims

In this experiment you will observe the reaction between aqueous solutions of the halogens and solutions of the metal halide salts. A more reactive halogen will displace a less reactive halogen from its metal halide salt. These displacement reactions can be used to establish an order of reactivity down Group 7 of the periodic table.

Safety

Chlorine water is harmful and bromine water is toxic. Tell your teacher if you spill either of these chemicals on your skin.

Cyclohexane is highly flammable and harmful so make sure there are no naked flames around while you are using it.

Wear chemical splash-proof eye protection when carrying out this experiment. Dispose of chemicals as instructed.

Method

1 Pour about 2 cm3 of each of the aqueous halogen solutions (chlorine water, bromine water, iodine solution) into separate test tubes. Add 1 cm3 of cyclohexane to each tube, stopper the tube and, holding your thumb over the bung, shake the mixture by inverting the test tube a few times.

2 Allow the two layers to settle. The cyclohexane will be the top layer (organic layer). Observe the colour of each layer and record this in the table below. It may be necessary to shake the test tubes again to transfer more of the halogen from the water to the hydrocarbon layer.

3 Pour about 2 cm3 of each of the aqueous halogen solutions into separate test tubes. Add 2 cm3 of potassium chloride to each tube and then 1 cm3 of cyclohexane, stopper the tube and, holding your thumb over the bung, shake the mixture by inverting the test tube a few times.

4 Observe the colour of the organic cyclohexane layer (top) and record in the table below.5 Observe the colour of the aqueous layer (bottom) and record in the table below6 Repeat steps 3 and 4 with potassium bromide and potassium iodide.

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Organic Layer (containing Halogen)

Aqueous Layer (containing Halide Ion)

Results

Chlorine Water Bromine Water Iodine Water

Potassium ChlorideO - O -

Aq - Aq -

Potassium BromideO - O -

Aq - Aq -

Potassium IodideO - O -

Aq - Aq -

Questions

What is the purpose of first carrying out the experiment in steps 1 and 2 without the halide?

Which combinations of aqueous halogen and metal halide solution reacted? Give evidence to support your answer.

Write a balanced symbol equations for any reactions that occurred in steps 3–5 of the practical.

Which halogen displaced all the other halogens from solutions of their salts?

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Write a list of the halogens you used putting them in order of reactivity with the most reactive first.

Extend the list that you made in Question 5 to include all the Group 7 elements.

Write an ionic equation for the reaction between chlorine and iodide ions.

Group 7 ReactivityComplete the electronic configuration for the first three elements in group 7 and write and explanation for the

pattern of reactivity in terms of their atomic structure

Electronic Configuration Reactivity Explanation

*Outer shell only

L8 – Group 0 (The Noble Gases)

Draw the Electronic Configuration for the first 3 Noble Gases

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Helium Neon Argon

Read the information below, complete the table and answer the questions

Element Symbol Colour Boiling Point Uses

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Helium

Neon

Argon

Krypton

Xenon

Questions

What does monatomic mean?

How would you describe the reactivity of the Noble Gases?

What happens to the size of the atoms as you go down the group?

What happens to the boiling point as you go down the group?

Why does this happen?

What can be said about the outer shell of each noble gas?

Which is the least dense noble gas?

What does Inert mean?

Personalised Learning Checklist AQA Chemistry (9-1) Paper 2 - Topic 8 Chemical Analysis

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Topic Student Checklist R A G

4.8.

1 P

urity

, for

mul

ation

s and

ch

rom

atog

raph

& 4

.8.2

ID

of g

ases

Define a pure substance and identify pure substances and mixtures from data about melting and boiling points Describe a formulation and identify formulations given appropriate information Describe chromatography, including the terms stationary phase and mobile phase and identify pure substances using paper chromatography Explain what the Rf value of a compound represents, how the Rf value differs in different solvents and interpret and determine Rf values from chromatograms Required practical 6: investigate how paper chromatography can be used to separate and tell the difference between coloured substances (inc calculation of Rf values) Explain how to test for the presence of hydrogen, oxygen, carbon dioxide and chlorine

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Just Learn Facts – These are facts that you need to learn Processes – Make sure you can complete all of these tasks

In chemistry, a pure substance is a single element or compound, not mixed with any other substance.Pure elements and compounds melt and boil at specific temperatures. Melting point and boiling point data can be used to distinguish pure substances from mixtures. In everyday language, a pure substance can mean a substance that has had nothing added to it, so it is unadulterated and in its natural state, e.g. pure milk.

A formulation is a mixture that has been designed as a useful product. Many products are complex mixtures in which each chemical has a particular purpose. Formulations are made by mixing the components in carefully measured quantities to ensure that the product has the required properties. Formulations include fuels, cleaning agents, paints, medicines, alloys, fertilisers and foods.

Chromatography can be used to separate mixtures and can give information to help identify substances. Chromatography involves a stationary phase and a mobile phase. Separation depends on the distribution of substances between the phases. In paper chromatography a solvent moves through the paper carrying different compounds different distances, depending on their attraction for the paper and the solvent. The ratio of the distance moved by a compound (centre of spot from origin) to the distance moved by the solvent can be expressed as its Rf value:

R f=distancemoved by substancedistancemovedby solvent

Different compounds have different Rf values in different solvents, which can be used to help identify the compounds. The compounds in a mixture may separate into different spots depending on the solvent but a pure compound will produce a single spot in all solvents.

The test for hydrogen uses a burning splint held at the open end of a test tube of the gas. Hydrogen burns rapidly with a pop sound.The test for oxygen uses a glowing splint inserted into a test tube of the gas. The splint relights in oxygen.The test for carbon dioxide uses an aqueous solution of calcium hydroxide (lime water). When carbon dioxide is shaken with or bubbled through limewater the limewater turns milky (cloudy).The test for chlorine uses litmus paper. When damp litmus paper is put into chlorine gas the litmus paper is bleached and turns white.

Summarise the key definitions in a table of element, compound, mixture, pure substance, impure substance.

Explain how impurities increase the boiling point and lower the melting point.

Explain the difference between a mixture and a formulation.

Recall the functions of key components in formulations.

Draw a labelled diagram to explain how to carry out paper chromatography.

Draw a flow map to explain how substances dissolve in the mobile phase, are adsorbed onto the stationary phase and are separated.

Practise interpreting chromatograms and working out Rf values.

Identify pure / impure substances from chromatograms.

Draw labelled diagrams / flow maps to explain how to do each gas test and the results expected.

Practise identifying gasses evolved from experimental data given.

L1 – Pure / Impure Substances

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All: Recall the definitions of a pure substance, compound and mixture.Most: Use melting / boiling point data to distinguish between pure and impure substances.

Some: Explain in terms of intermolecular forces, melting and boiling points.

Look at the particle pictures below and identify which are:1. Pure elements

2. Pure compounds3. Impure mixtures

A-

B-

C-

D-

E-

F-

G-

H-

I-

Choose the correct word:Impurities increase / decrease the boiling point of a substance.Impurities increase / decrease the melting point of a substance.

Explain why we grit (add salt to) our roads in winter

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L2 – Formulations

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All: Explain the difference between a mixture and a formulation and give examples of different formulations.Most: Describe the purpose of each chemical in a formulation.

Some: Identify formulations given appropriate information.

Formulations often include the following:

Write down the function of each ingredient in table below – There are clues on the next page if required:

Ingredient Function

Pigment / Colourant

Solvent

Binder / Emulsifier

Preservatives/ Antioxidants

/ Bactericides / Fungicides / Algaecides

Buffering agents

Antifoaming agents

Enzymes

Protease / Amylase / Lipase

Flavours

Lubricant

Ignition Improver

Clues:

Controls the pH Liquid that key ingredients are

Holds the substance together

Improves the taste Lowers the temperature required

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dissolved in for ignition

Prevents the product from going off due to a chemical reaction

Prevents the product from foaming

Provides the correct colour

Reduces friction between objects that rub or slide past each

other

Stain remover – breaks down,

proteins, fats, etc.

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Grade 4/5 Grade 6/7 Grade 8/9

Explain what a formulation is. Describe the different functions of chemicals found in different

formulations.

Choose the best formulation from information given and explain your

choice.

L3 – Chromatography

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All: Describe how to carry out simple paper chromatography.Most: Explain how the different substances are separated using chromatography with reference to their solubility in the

mobile phase and adsorption onto the stationary phase.Some: Describe how Rf values can be calculated, interpret chromatograms and calculate Rf values.

Draw a mind map for the uses of Chromatography below:

Draw a flow map to explain how the dyes travel up the paper using the words;

adsorb, dissolve, mobile phase, stationary phase, soluble, solvent.

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Write down how we calculate the Rf value from chromatograms, include a labelled diagram:

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Q2.A student investigated food dyes using paper chromatography.

This is the method used.

1.       Put a spot of food colouring X on the start line.2.       Put spots of four separate dyes, A, B, C and D, on the start line.3.       Place the bottom of the paper in water and leave it for several minutes.

Figure 1 shows the apparatus the student used.

Figure 1

 

(a)     Write down two mistakes the student made in setting up the experiment and explain what problems one of the

mistakes would cause.

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(2)

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(b)     Another student set up the apparatus correctly.

Figure 2 shows the student’s results. The result for dye D is not shown.

Figure 2

 

Calculate the Rf value of dye A

Give your answer to two significant figures.

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Rf value = ______________________(3)

(c)     Dye D has an Rf value of 0.80. Calculate the distance that dye D moved on the chromatography paper.

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Distance moved by dye D = ______________________(1)

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(d)     Explain how the different dyes in X are separated by paper chromatography.

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EXTENSION

(e)     Flame emission spectroscopy can be used to analyse metal ions in solution.

Figure 3 gives the flame emission spectra of five metal ions, and of a mixture of two metal ions.

Figure 3

 

Use the spectra to identify the two metal ions in the mixture.

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(f)     Explain why a flame test could not be used to identify the two metal ions in the mixture.

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(g)     Two students tested a green compound X.The students added water to compound X.Compound X did not dissolve.

The students then added a solution of ethanoic acid to compound X.A gas was produced which turned limewater milky.

Student A concluded that compound X was sodium carbonate.Student B concluded that compound X was copper chloride.

Which student, if any, was correct?

Explain your reasoning.

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Describe how to carry out simple paper chromatography.

Explain how the different substances are separated using

chromatography with reference to their solubility in the mobile phase and adsorption onto the stationary

phase.

Describe how Rf values can be calculated, interpret

chromatograms and calculate Rf

values.

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L4 – Required Practical 5 – Paper Chromatography

All: Carry out a simple paper chromatography investigation.Most: Calculate Rf Values and draw conclusions

Some: Evaluate the experiment and suggest improvements.

Which chromatogram above is better and so used the better solvent?

Explain your answer:

Chromatography Required Practical

Read through the required practical, make sure you understand the following

-Risk Assessment-Equipment Used

-Method-Results

Carry out steps 1-8 and complete the Results Table

Create a flow map showing how to carry out this practical and obtain results

Answer the Example Questions

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L4 – Gas Tests

All: Describe the tests for Hydrogen, Oxygen, Carbon Dioxide and Chlorine Gas.Most: Carry out the tests for Hydrogen, Oxygen, Carbon Dioxide and Chlorine Gas.

Some: Identify the gases evolved from given data.In the boxes below, summarise how you test for each gas in a table.

You must include: A labelled diagram, step by step method and expected observations if the test is positive:

Hydrogen Oxygen

Carbon Dioxide Chlorine

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In the experiment above Hydrogen and another unknown gas was produced which bleached litmus paper.

1. What is the name of the gas that bleached the litmus paper?

__________________

2. Describe how we could test for Hydrogen gas and the expected positive result:

____________________________________

In the experiment on the left the Metal Carbonate was heated and produced a Metal Oxide and an unknown

gas.

The limewater changed from colourless to cloudy, what is the name of the unknown gas?

______________

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Personalised Learning Checklist

AQA Chemistry (9-1) Paper 1 – Topic 2 Bonding, structure, and the properties of matterTopi

c Student Checklist R A G

4.2.

1 C

hem

ical

bon

ds, i

onic

, cov

alen

t and

met

allic

Describe the three main types of bonds: ionic bonds, covalent bonds and metallic bonds in terms of electrostatic forces and the transfer or sharing of electrons

Describe how the ions produced by elements in some groups have the electronic structure of a noble gas and explain how the charge of an ion relates to its group number

Describe the structure of ionic compounds, including the electrostatic forces of attraction, and represent ionic compounds using dot and cross diagrams

Describe the limitations of using dot and cross, ball and stick, two and three-dimensional diagrams to represent a giant ionic structure

Work out the empirical formula of an ionic compound from a given model or diagram that shows the ions in the structure

Describe covalent bonds and identify different types of covalently bonded substances, such as small molecules, large molecules and substances with giant covalent structures

Represent covalent bonds between small molecules, repeating units of polymers and parts of giant covalent structures using diagrams

Draw dot and cross diagrams for the molecules of hydrogen, chlorine, oxygen, nitrogen, hydrogen chloride, water, ammonia and methane

Deduce the molecular formula of a substance from a given model or diagram in these forms showing the atoms and bonds in the molecule

Describe the arrangement of atoms and electrons in metallic bonds and draw diagrams the bonding in metals

4.2.

2 H

ow b

ondi

ng a

nd st

ruct

ure

are

rela

ted

to th

e pr

oper

ties o

f su

bsta

nces

Name the three States of matter, identify them from a simple model and state which changes of state happen at melting and boiling points

Explain changes of state using particle theory and describe factors that affect the melting and boiling point of a substance

HT ONLY: Discuss the limitations of particle theory

Recall what (s), (l), (g) and (aq) mean when used in chemical equations and be able to use them appropriately

Explain how the structure of ionic compounds affects their properties, including melting and boiling points and conduction of electricity (sodium chloride structure only)

Explain how the structure of small molecules affects their properties Explain how the structure of polymers affects their properties Explain how the structure of giant covalent structures affects their properties Explain how the structure of metals and alloys affects their properties, including explaining why they are good conductors

Explain why alloys are harder than pure metals in terms of the layers of atoms

Explain the properties of graphite, diamond and graphene in terms of their structure and bonding

Describe the structure of fullerenes, and their uses, including Buckminsterfullerene and carbon nanotubes

Chem ONLY: Compare the dimensions of nanoparticles to other particles and explain the affect of their surface area to volume ratio on their properties

Chem ONLY: Discuss the applications of nanoparticles and their advantages and disadvantages, including uses in medicine, cosmetics, fabrics and the development of catalysts

61

Just Learn Facts – These are facts that you need to learnProcesses – Make sure you can complete all

of these tasks

Compounds are substances in which 2 or more elements are chemically combined

Ionic bonds are formed between metals and non-metals Metals lose electron(s) and form positive ions Non-metals gain electron(s) and form negative ions Ionic compounds are formed by a strong electrostatic attraction between oppositely charged ions.

The force works in all directions Ionic compounds form a giant lattice structure Ionic compounds have a high melting point as the electrostatic attraction is strong Ionic compounds do not conduct as a solid as the ions are not free to move Ionic compounds conduct electricity when molten or in solution as the ions are free to move and

carry the current.

Metals are layers of positive metal ions surrounded by free delocalised electrons The ions can slide over each other so metals can be hammered into shape Metals can conduct electricity and heat Alloys are usually made from 2 or more metals. The different size atoms distort the layers stopping

them from rolling over each other making the alloy stronger

Covalent bonds are formed between 2 non-metals The non-metals share pairs of electrons to form the bond Simple covalent molecules are small molecules and have low melting and boiling points due to the

weak intermolecular forces between the molecules Simple covalent molecules do not conduct electricity as they have no free moving electrons

Polymers are made of long chains linked by strong covalent bonds Polymers are formed when many monomers break their double bond and join together to make a

polymer The intermolecular forces between the chains get bigger as the chain gets longer

In Giant covalent structures (macromolecules) all the atoms are linked by strong covalent bonds and have very high melting points

In diamond each carbon makes 4 bonds to other carbons so diamond is hard In graphite the carbons form layers with 3 covalent bonds to other carbons. This makes graphite soft

as the layers can roll over each other Graphite can conduct electricity and heat as it has free delocalised electrons to carry the current

Graphene is a single layer of graphite so is one atom thick Fullerenes are molecules of carbon with hollow shapes. The structure is based on hexagonal rings of

carbon atoms Carbon nanotubes are cylindrical fullerenes. They have a high tensile strength and high electrical and

thermal conductivity

The 3 states of matter are solid, liquid and gas The amount of energy needed to change state depends on the strength of the forces between the

particles The stronger the forces between the particles the higher the melting point Limitations of the particle model:

The particles are not all solid spheresThe model doesn’t show forces between the spheres

Draw the ionic bond between sodium chloride, magnesium oxide and calcium chloride

Explain why metals can conduct electricity

Give examples of where alloys are used

Draw dot cross diagrams for the bonds in water, ammonia, hydrogen, hydrogen chloride,

Draw a diagram showing ethane forming polyethene

Make a double bubble map comparing diamond and graphite

List examples of uses of fullerenes and carbon nanotubes

Draw diagrams representing solids, liquids and gases

List the key words to describe each change in state

L1 – Writing ionic formula and ionic bonding

62

All: Explain how ionic bonds are formed.Most: Draw the formation of an ionic bond.

Some: Represent ionic bonds between atoms with different charges.

Starter: Make a tree map recapping the structure if the atom

What could cause an atom to have a negative overall charge?

What could cause an atom to have a positive overall charge?

Definition of an Ion

An ion is an element that has either lost or gained electrons to become a either positively or negatively charged

63

The Atom

Mass = Charge = Position =

Mass = Charge = Position =

Mass = Charge = Position =

SODIUM ION2,8

Na+

Cl

CHLORIDE ION2,8,8

Cl

SODIUM ATOM2,8,1

Na

CHLORINE ATOM2,8,7

F19

9F-

19

9

Explain how an ionic bond is formed (3)

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

Ionic bonding occurs between and .

The metal atoms electrons to form ions with a charge.

The non metal atoms electrons to form ions with a charge.

These ions are charged and so have a electrostatic attraction between

them.

This attraction requires a lot of energy to break and so ionic compounds have melting and boiling

points.

Summarise Ionic Bonding in less than 10 words (it doesn’t have to be a complete sentence)

Flow map

64

Draw a flow map for the formation of ionic bond

Cation Anion Compound

Na+ Cl- NaCl

Na+ O2- Na2O

Mg2+ O2- MgO

Mg2+ Cl- MgCl2

What’s the Link between the Charge of the Ions and the Formula of the compound?

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

Use the formula to write the ions and formula of the compounds

65

Compound Positive Ion Negative Ion Formula

Potassium Chloride K+ Cl- KCl

Lithium Bromide Li+ Br-

Magnesium Oxide Mg2+ O2-

Calcium Chloride CaCl2

Aluminium Iodide Al3+ I-

Aluminium Oxide Al2O3

Sodium Hydroxide Na+ OH-

Copper (II) Sulphate Cu2+ SO42- CuSO4

Silver Nitrate Ag+ NO3-

Calcium Carbonate Ca2+ CO32-

Sodium Hydrogen Carbonate Na+ HCO3-

Magnesium Hydroxide Mg(OH)2

Ionic Bonding Assessment

Explain how Lithium and Fluorine bond together to form Lithium Fluoride (5 marks)

Work out the mark scheme, write down what you think scores each mark.

1

2

3

4

5

Magnesium is in group 2 and has 12 electrons, Oxygen is in group 6 and has 8 electrons.Draw dot and cross diagrams explaining how Magnesium and Oxygen bond together to form Magnesium Oxide (5 marks)

66

L2 – Properties of Ionic Compounds

All: Identify an ionic structure diagram.Most: Explain the properties of ionic compounds.

Some: Link the properties of ionic compounds to their structure.

Make a bubble map of the properties of ionic compounds and add to it during the lesson

Frame of Reference : Structure and Bonding

Most ionic compounds dissolve in water and when they do the solution will conduct electricity. You are going to test six substances to see if they are ionic compounds.

67

Properties of Ionic

Compounds

PredictionWhich of the test substances do you think are ionic compounds, and why?

Apparatus eye protection boiling tube & bung beaker 2 × graphite electrodes

leads & crocodile clips lamp in a holder d.c. power supply small spatula teat pipette

substances to test – sodium chloride, potassium iodide, ethanol, sugar, copper sulfate and water

Health and safety● Eye protection should be used.

● Ethanol is harmful and highly flammable.

● Toxic fumes may be produced so do not keep the circuit connected for too long.

● Toxic gases, eg, chlorine, may be produced. Asthmatics need to take extra care. As there is no reason to collect gases, once the observations have been made the circuit should be switched off.

Method1. Fit the graphite electrodes into the beaker.

2. Connect the circuit as shown in the diagram. Identify which rod is the positive electrode and which is the negative electrode. Test your circuit by briefly touching the electrodes together or briefly touching the ends of a lead to them.

3. Add water so that the electrodes are partly submerged.

4. Observe and record whether the lamp lights, and any changes at each electrode. Empty the beaker.

5. Choose one of the test substances.

6. Pour the solution into the beaker.

7. Observe and record whether the lamp lights or not. Empty the beaker and clean the apparatus.

8. Repeat steps E, F and G with the remaining substances.

Substance Does the lamp light? Observations

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Water

Copper Sulfate

Ethanol

Potassium iodide

Sodium Chloride

Sugar

Link each of the following properties with the correct explanation

High Melting Point Ions are free to move and carry the current

Doesn’t Conduct electricity when solid

Ions are arranged in a regular repeating pattern

Conducts electricity when molten or dissolved

Strong attractions between oppositely charged ions in a Giant

Lattice

Regular shaped crystals Ions are in fixed positions and cannot move

69

Exam Questions

Explain why ionic substances have high melting and boiling points. (2)

Explain why ionic substances can conduct electricity when melted or dissolved. (2)

Explain why ionic substances cannot conduct electricity when solid. (2)

The diagram below shows the ions in solid sodium chloride. Re-draw the diagram to show how the ions would be arranged if the sodium chloride was melted. (2)

Write the formula of the following ionic compounds.

Calcium Chloride - Aluminium hydroxide -

Sodium Oxide - Potassium Carbonate -

Magnesium Sulphide - Calcium Nitrate -

70

Complete the passage below using the following words:loses ions ionic protons negative electrons positive gains

Atoms are neutral because they have the same number of ………………….. and ………………… . If atoms lose or

gain electrons they become electrically charged and are called ………… (they are not atoms any more). If

atoms gain electrons they become ……………….... ions, and if they lose electrons they become …………………

ions. When a metal reacts with a non-metal, the metal atoms …………….. electrons and the non-metal atoms

…………… electrons, forming an ……………….. compound.

Complete the table about the metals below

Element Na K Mg Ca Al

Group Number

Number of Valence Electrons

Charge of Ion Formed

What do you notice about the Group number and the charge on the ions for metals? (1)

Complete the table about the metals below

Element Cl Br I O S

Group Number

Number of Valence Electrons

Charge of Ion Formed

What do you notice about the Group number and the charge on the ions for non-metals? (1)

Write the electron configuration for the following ions (4)

71

Na+ Ca2+ S2- F-

What do you think would be the charge on ions formed from the following elements? (3)

Strontium (Sr) - Tin (Sn) - Astatine (At) -

Tick which diagram(s) correctly show an ionic compound? (1)

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L3 – Metallic Structure and Alloys

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All: Describe metallic structure.Most: Explain the properties of metals.

Some: Explain the difference between metals and alloys.

Draw a bubble map for all the common properties of metals

Describe what you can see in the diagram

_____________________________________

_____________________________________

_____________________________________

Practical Results

Substance Conducts electricity? Conducts heat?

Graphite

Wood

Plastic

Metal

Justify why copper is used in the centre of a wire and why plastic is used around the wire (3)

_________________________________________________________________________

_________________________________________________________________________

_________________________________________________________________________

Look at the table below, silver conducts better than copper. Why is it not used in wires?

73

Metal Conductivity ( σ (S/m) at 20 °C)

Silver 6.30×107

Copper 5.96×107

Pure iron is too soft to be useful as a building material. Steel is iron with small amounts of carbon added. Alloy steels are

made by mixing iron or steel with other metals.

Type What it contains Properties Relative cost

pure iron iron soft and weak Low

steel (low carbon)iron

+ about 0.1% carbon

harder and stronger than iron but easily

shapedLow

steel (high carbon)iron

+ about 1% carbonharder but morebrittle than steel

Low

stainless steelIron + 18% chromium

+ 10% nickel

hard and very resistant

to corrosionHigh

titanium steeliron

+ 0.5–2% titanium

able to withstandvery high

temperaturesHigh

manganese steeliron

+ 14% manganeseextremely hard High

1 Which of the metals or alloys listed in the table are alloy steels?

________________________________________________________________________________

_

2 Use the information in the table to choose the best steel for each of the following uses and give

reasons.

a Paper Clips

________________________________________________________________________________

________________________________________________________________________________

b Cutlery

________________________________________________________________________________

________________________________________________________________________________

c Cooker Tops

________________________________________________________________________________

74

d Razor Blades

________________________________________________________________________________

________________________________________________________________________________

e ‘Points’ for railway lines (to guide trains from one track to another)

________________________________________________________________________________

________________________________________________________________________________

f Engine parts that have to operate at very high temperatures.

________________________________________________________________________________

________________________________________________________________________________

1. Explain why a metal is a good conductor of electricity and heat]

2. Explain why an alloy is stronger than a metal

3. Name two other properties that can change when making an Alloy

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Exam Questions

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77

78

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L4 – Covalent Bonding

All: Draw dot/cross diagrams for molecules with single bonds.Most: Describe the limitations of using models to represent molecules.

Some: Deduce the molecular formula of a substance from a given model or diagram.

Starter: Make a double bubble map comparing ionic and metallic bonding

Explain how the following would achieve a full outer shell

81

What are the advantages and disadvantages of representing covalent bonds in the different ways?

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

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_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

_________________________________________

82

Define a Covalent Bond -

Draw Dot and Cross Diagrams for the following

F2 HF CH4

H2O SiCl4 NH3

O2 CO2 N2

HCN H2CO C2H4

83

L5 – Properties of Simple Covalent Compounds

All: Explain the properties of simple covalent compounds.Most: Explain how boiling point changes with size of the molecule.

Some: Explain the properties of polymers.

If these are the answers, what could the Chemistry questions be?

1. Molecules

2. A covalent bond

3. An ionic bond

4. Electrons

5. Metals

6. Non-metals

From the demonstrations:

The boiling point of simple covalent compounds is_________ because________________________________

__________________________________________________________________________________________

Covalent compounds ________________ conduct electricity because_________________________________

__________________________________________________________________________________________

84

Explain what happens to the chlorine liquid in a chlorine gas bomb when it explodes

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

Explain the effect of the chain length of polymers on the boiling point and melting point

____________________________________________

____________________________________________

____________________________________________

____________________________________________

____________________________________________

____________________________________________

Name the type of bonding present in the different compounds.

Substance Melting Point Boiling Point Conductivity Type Of Bonding

A -56°c 37°c None

B 536°c 1034°c Conducts as a solid and liquid

C 734°c 1035°cConducts as liquid

and in solution, not as solid

D 935°c 2178°c Conducts as a solid and liquid

E 2600°c 2853°c Conducts only as liquid and in solution

F 76°c 157°c None

85

Exam Questions

86

87

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L6 – Diamond and Graphite

All: Describe some difference between the giant covalent and simple molecular structures.Most: Explain the differences in the physical properties of giant covalent and simple molecular substances.

Some: Explain the difference in the physical properties of giant covalent and simple molecular substances and link this to their uses.

What’s wrong with this picture?

_________________________________________

_

_________________________________________

_

_________________________________________

_

_________________________________________

_

_________________________________________

_

In pairs list everything you know about diamond and graphite:

Diamond Graphite

90

Complete the table showing the Properties, Structure and Used of Diamond and Graphite

Allotrope Structure and Bonding Properties Uses

Diamond

91

Graphite

Q1.Graphite and diamond are different forms of the element carbon.

Graphite and diamond have different properties.

The structures of graphite and diamond are shown below.

Graphite Diamond

(a)     Graphite is softer than diamond.

Explain why.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

92

___________________________________________________________________

___________________________________________________________________

(4)

(b)     Graphite conducts electricity, but diamond does not.

Explain why.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

(3)

L7 – Graphene, Fullerenes and Nanotubes

All: Describe what graphene and fullerenes are.Most: Explain how the properties of nanoparticles affect their uses.

Some: Give examples of uses of fullerenes and nanotubes.

What is a nanoparticle?

_____________________________________________________________________________________

Complete the table below showing the properties and Uses of Carbon Nanonparticles

Allotrope Structure and Bonding Properties Uses

Graphene

93

Carbon Nanotubes

Fullerene

94

L8 – States of Matter

All: Predict the state of a substance at different temperatures.Most: Explain what happens as a substance changes state.

Some: Explain the limitations of the particle model.

Draw structures of a solid, liquid and gas and name each change of state:

95

Explain what happen when an ice cube is heated until it forms steam. Include diagrams of the particles at each

stage

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

Create flow maps explaining how different substances are melted based on their structure and bonding, think about the forces of attraction and types of particles involved in each substance

96

Iron Metal (Fe)

Sodium Chloride (NaCl)

Glucose (C6H12O6)

Explain the limitations of the particle model when explaining the melting point of water and sodium chloride

97

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

Exam Questions

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99

100

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Personalised Learning Checklist AQA Chemistry (9-1) Paper 2 – Topic 7 Organic chemistry

Topic Student Checklist R A G

4.7.

1 C

arbo

n co

mpo

unds

as f

uels

and

feed

stoc

k

Describe what crude oil is and where it comes from, including the basic composition of crude oil and the general chemical formula for the alkanes State the names of the first four members of the alkanes and recognise substances as alkanes from their formulae Describe the process of fractional distillation, state the names and uses of fuels that are produced from crude oil by fractional distillation Describe trends in the properties of hydrocarbons, including boiling point, viscosity and flammability and explain how their properties influence how they are used as fuels Describe and write balanced chemical equations for the complete combustion of hydrocarbon fuels Describe the process of cracking and state that the products of cracking include alkanes and alkenes and describe the test for alkenes Balance chemical equations as examples of cracking when given the formulae of the reactants and products Explain why cracking is useful and why modern life depends on the uses of hydrocarbons

103

104

Just Learn Facts – These are facts that you need to learn.

Processes.Make sure you can

complete all of these tasks.

Crude oil is a finite resource found in rocks. Crude oil is the remains of an ancient biomass consisting mainly of plankton that was buried in mud. Crude oil is a mixture of a very large number of compounds. Most of the compounds in crude oil are hydrocarbons, which are molecules made up of hydrogen and carbon atoms only.

Most of the hydrocarbons in crude oil are hydrocarbons called alkanes. The general formula for the homologous series of alkanes is CnH2n+2The first four members of the alkanes are methane, ethane, propane and butane.Alkane molecules can be represented in the following forms:C2H 6 or

The many hydrocarbons in crude oil may be separated into fractions, each of which contains molecules with a similar number of carbon atoms, by evaporating the oil and allowing it to condense at different temperatures. This process is called fractional distillation.The fractions can be processed to produce fuels and feedstock for the petrochemical industry. Many of the fuels on which we depend for our modern lifestyle such as petrol, diesel oil, kerosene, heavy fuel oil and liquefied petroleum gases, are produced from crude oil.Many useful materials on which modern life depends are produced by the petrochemical industry, such as solvents, lubricants, polymers, detergents.

Some properties of hydrocarbons depend on the size of their molecules, including boiling point and viscosity which increase with increasing molecular size and flammability which decreases with increasing molecular size. These properties influence how hydrocarbons are used as fuels.

The combustion of hydrocarbon fuels releases energy. During combustion, the carbon and hydrogen in the fuels are oxidised. The complete combustion of a hydrocarbon produces carbon dioxide and water.

Hydrocarbons can be broken down (cracked) to produce smaller, more useful molecules. This process involves heating the hydrocarbons to vaporise them. The vapours are either passed over a hot catalyst or mixed with steam and heated to a very high temperature so that thermal decomposition reactions then occur.

The products of cracking include alkanes and another type of hydrocarbon called alkenes.Alkenes are more reactive than alkanes and react with bromine water, turning it from orange to colourless.There is a high demand for fuels with small molecules and so some of the products ofcracking are useful as fuels.Alkenes are used to produce polymers and as starting materials for the production of many other chemicals.

Make a flow map to describe how crude oil is formed

Make a flow map to explain how crude oil; is separated using fractional distillation

Write balanced equations for the complete combustion of hydrocarbons with a given formula.

Balance chemical equations as examples of cracking given the formulae of the reactants and products.

L1 – Crude Oil and Alkanes

All Describe the formation and composition of crude oilMost Explain what is meant by a saturated hydrocarbon

Some Deduce the formula of hydrocarbons from the general formula CnH2n+2

Draw a flow map to explain how crude oil was formed

Personalised Learning Checklist AQA Chemistry (8462) from 2016 Topics C4.9 Chemistry of the atmosphere

Topic Student Checklist R A G

4.9.

1 T

he co

mpo

sition

and

ev

oluti

on o

f the

Ear

th's

Describe the composition of gases in the Earth's atmosphere using percentages, fractions or ratios

Describe how early intense volcanic activity may have helped form the early atmosphere and how the oceans formed

Explain why the levels of carbon dioxide in the atmosphere changes as the oceans were formed

State the approximate time in Earth's history when algae started producing oxygen and describe the effects of a gradually increasing oxygen level

Explain the ways that atmospheric carbon dioxide levels decreased

4.9.

2 C

arbo

n di

oxid

e an

d m

etha

ne a

s gre

enho

use

gase

s

Name some greenhouse gases and describe how they cause an increase in Earth's temperature

List some human activities that produce greenhouse gases

Evaluate arguments for and against the idea that human activities cause a rise in temperature that results in global climate change

State some potential side effects of global climate change, including discussing scale, risk and environmental implications

Define the term carbon footprint and list some actions that could reduce the carbon footprint

4.9.

3 C

omm

on

atm

osph

eric

pol

luta

nts Describe the combustion of fuels as a major source of atmospheric pollutants and name the different gases

that are released when a fuel is burned

Predict the products of combustion of a fuel given appropriate information about the composition of the fuel and the conditions in which it is used

Describe the properties and effects of carbon monoxide, sulfur dioxide and particulates in the atmosphere

Describe and explain the problems caused by increased amounts of these pollutants in the air

105

106

Just Learn Facts – These are facts that you need to learn.Processes.

Make sure you can complete all of these tasks.

For 200 million years, the proportions of different gases in the atmosphere have been much the same as they are today:

Approximately 80% NitrogenApproximately 20% OxygenSmall proportions of various other gases, including carbon dioxide, water vapour and noble gases.

Theories about what was in the Earth’s early atmosphere and how the atmosphere was formed have changed and developed over time. Evidence for the early atmosphere is limited because of the time scale of 4.6 billion years. One theory suggests that during the first billion years of the Earth’s existence there was intense volcanic activity that released gases that formed the early atmosphere and water vapour that condensed to form the oceans. At the start of this period the Earth’s atmosphere may have been like the atmospheres of Mars and Venus today, consisting of mainly carbon dioxide with little or no oxygen gas. Volcanoes also produced nitrogen which gradually built up in the atmosphere and there may have been small proportions of methane and ammonia. When the oceans formed carbon dioxide dissolved in the water and carbonates were precipitated producing sediments, reducing the amount of carbon dioxide in the atmosphere. No knowledge of other theories is required.

Algae and plants produced the oxygen that is now in the atmosphere by photosynthesis, which can be represented by the equation:

Algae first produced oxygen about 2.7 billion years ago and soon after this oxygen appeared in the atmosphere. Over the next billion years plants evolved and the percentage of oxygen gradually increased to a level that enabled animals to evolve

Greenhouse gases in the atmosphere maintain temperatures on Earth high enough to support life. Water vapour, carbon dioxide and methane are greenhouse gases.

Algae and plants decreased the percentage of carbon dioxide in the atmosphere by photosynthesis.Carbon dioxide was also decreased by the formation of sedimentary rocks and fossil fuels that contain carbon.

Some human activities increase the amounts of greenhouse gases in the atmosphere. These include:Carbon dioxide and methane.

Students should be able to recall two human activities that increase the amounts of each of the greenhouse gases carbon dioxide and methane. Based on peer-reviewed evidence, many scientists believe that human activities will cause the temperature of the Earth’s atmosphere to increase at the surface and that this will result in global climate change. However, it is difficult to model such complex systems as global climate change. This leads to simplified models, speculation and opinions presented in the media that may be based on only parts of the evidence and which may be biased

An increase in average global temperature is a major cause of climate change. There are several potential effects of global climate change.

The carbon footprint is the total amount of carbon dioxide and other greenhouse gases emitted over the full life cycle of a product, service or event. The carbon footprint can be reduced by reducing emissions of carbon dioxide and methane.

The combustion of fuels is a major source of atmospheric pollutants. Most fuels, including coal, contain carbon and/or hydrogen and may also contain some sulphur. The gases released into the atmosphere when a fuel is burned may include carbon dioxide, water vapour, carbon monoxide, sulphur dioxide and oxides of nitrogen. Solid particles and unburned hydrocarbons may also be released that form particulates in the atmosphere.

Carbon monoxide is a toxic gas. It is colourless and odourless and so is not easily detected. Sulphur dioxide and oxides of nitrogen cause respiratory problems in humans and cause acid rain. Particulates cause global dimming and health problems for humans.

Describe the main changes in the atmosphere over time and some of the likely causes of these changes

Describe and explain the formation of deposits of limestone, coal, crude oil and natural gas.

Describe the greenhouse effect in terms of the interaction of short and long wavelength radiation with matter.

Interpret appropriate information and evaluate different theories about the Earth’s early atmosphere.

Evaluate the quality of evidence in a report about global climate change given appropriate information

Describe uncertainties in the evidence base

Recognise the importance of peer review of results and of communicating results to a wide range of audiences.

Describe briefly four potential effects of global climate change

Discuss the scale, risk and environmental implications of global climate change.

Describe actions to reduce emissions of carbon dioxide and methane

Give reasons why actions may be limited.

Describe how carbon monoxide, soot (carbon particles), sulphur dioxide and oxides of nitrogen are produced by burning fuels

Predict the products of combustion of a fuel given appropriate information about the composition of the fuel and the conditions in which it is used.

Describe and explain the problems caused by increased amounts of these pollutants in the air.

L1 – Earth’s Atmosphere

All: Identify the gases of the atmosphere

Most: Compare gases in the early atmosphere to today’s atmosphere

Some: Explain how the early atmosphere evolved