9-1 GCSE Combined ScienceKnowledge Organiser

Chemistry Y11 paper 2Topic 6 – Rate and extent of chemical changes Pg 100-114

Topic 7 – Organic Chemistry pg 115-121

Topic 8 – Chemical Analysis Pg 122-127

Topic 9 – Chemistry of the atmosphere pg 128-134

GCSE Chemistry Revision –Topic 6 – Factors affecting rates of reaction (p100-3)

Reactions can go at different rates.The rate of a reaction is how fast the _________ are changed into _____________

Reactants Products

Examples of slow reactions include•

•

Examples of fast reactions include•

Graphs for the rates of reaction

The steeper the line on the graph, the

_________ the rate of reaction.Over time the line becomes less steep because

____________________________________

Graph 4 shows that the reaction is ________

than the original reaction and that _______ products are made.

Factors affecting Rates of ReactionIn a nutshell, in order to react, particles must __________ with enough __________ for the reaction to happen.Any change which increases either of these things will increase the rate of reaction. There are FOUR things you can change:

1.

2.

3.

4.

Increasing the Temperature increases the rate because it makes the particles move _________This means they will _____________ more frequently and will have more ____________ .

Increasing Concentration or Pressure increases the rate because there are more ___________ in the same volume.This means they will collide more ___________

Increasing the Surface Area increases the rate because breaking up a solid increases its _________ ________ to ___________ ratio.

Because there is more area, there will be collisions ______ _____________

Using a Catalyst increases the rate without being _______ ____, so it is not part of the overall equation.

Different reactions need different catalyst.

An ______________ is an example of a biological catalyst.

The Rate of Reaction is worked out by using:

Amount of reactant used/product formedRate =

Time taken

If the chemical is a gas, measure amount in ____

If the chemical is solid, measure amount in ____

Time is measured in ___

Hence Rate is measured in _______ or _______

GCSE Chemistry Revision – Topic 6 Rates: Rates Experiments (p103-106)

Following (and measuring) Chemical reactions

1. Precipitation and Colour Change

If the solution is _____________ and the

product is a _______________ , we can look at a mark through the solution and time ________

____________________________________

This method is subjective

because ______________

_____________________

____________________________________

2. Change in Mass (because ____ is given off)

The cotton wool here because…

Taking measurements at regular intervals means we can…

This method is the most accurate because…

The quicker the reading on the balance drops…

3. The volume of gas given off (e.g Mg in acid)

Magnesium and dilute _____________ ______

react to produce ___________ gas

_______________ ________________

_______________

Investigating the effect of using differentacid concentrations – using Method 3

Method…

Conclusion…

Investigating the effect of using differentacid concentrations – using Method 1

Method

Results

Conclusion

Drawing a tangent…

1. Put the ruler on the graph at the pointyou want to know the rate.2. Adjust the ruler until ___________

_______________________________

_______________________________

3. Draw a line across the ruler to

make the _____________ . Extendthe line right across the graph.4. Pick two points that are easy toread.

change in yGradient =

Find the gradient of this tangent,

Answers 0.031 cm3/s (and graph C)

GCSE Chemistry Revision – Topic 6: Finding Reaction Rates from Graphs (p107)

Calculating the mean reaction rate from a graph

The mean reaction rate means the average rate for whole reaction to finish.

The reaction is finished when the line _______ _________ .

You can also find the mean rate between twotimes.

change in _____________Mean rate =

change in _____________

=

= _______ cm3/s

-

Draw a Tangent to find the Reaction Rate at a particular point

Reversible reactions can be Endothermic and Exothermic

If a reversible reaction is Exothermic in one

direction, it is ______________ in the other direction

Endothermic means that heat is transferred ___ the surroundings.Exothermic means that heat is transferred ___ the surroundings.

GCSE Chemistry Revision – Topic 6: Rates – Reversible Reactions (p110-112)

There are two types of equilibrium:

Static Equilibrium Dynamic EquilibriumWhere NOTHING is Where two things are

actually moving moving in opposite directions

Reversible Reactions will reach an Equilibrium

A + B ⇌ C + D

The “⇌” sign shows that ___ ________ _____

_____ _____

If we start with A and B, they will react

together to make C and D. The concentration of

A and B will ______ and the concentration of C

and D will ______ .

Therefore the rate at which A and B react

together will get _______ and the rate at which

C and D will react together will get _______ ….

At this point BOTH reactions are still happening,

but at the SAME _________

Another example of a Dynamic Equilibrium

If the RATE at which waterenters the tank is the SAMEas the RATE at which the water leaves the tank, thewater LEVEL will stay thesame.This is the POSITION ofEQUILIBRIUM

If you heat blue ____________ copper sulfate it drives the water off and leaves white

_____________ copper sulfate.N

o bea

rd

Henry Louis Le Chatelier

Inventor of the Principle which bears his name, he had insufficient facial hair to be classed as a proper Chemist, and spent his life being rejected by Chemistry Clubs

Le Chatelier’s Principle is used to predict what effect on the position of equilibrium will be caused by changing the CONDITIONS. The position will move to try to COUNTERACT the change…

Changing the TemperatureN2 + 3H2 ⇌ 2NH3

Here, the forward reaction is exothermic, so increasing the temp causes the position to move to counteract this and reduce the temp.The position will move in the endothermic temperature.

Hence the equilibrium moves to

the _______ and the amount

of NH3 in the final reaction

mixture _____________

Changing the PressureN2 + 3H2 ⇌ 2NH3

Here there are 4 moles of gas on the left and two on the right. Moving the position of equilibrium to the right will decrease the pressure.

Hence, if the pressure is

decreased, the equilibrium

moves to the ________ and

the amount of of NH3 in the

final reaction mixture

_____________

Changing the ConcentrationN2 + 3H2 ⇌ 2NH3

If you increase the concentration of N2 and H2

the position of equilibrium will move to decrease the concentration of N2 and H2

Hence, if the concentration

of N2 and H2 is increased, the

equilibrium moves to the

________ and the amount of

of NH3 in the final reaction

mixture _____________

KEY WORDS:

hydrocarbonalkane

homologous seriesgeneral formula

combustionoxidationdistillation

ASSESSMENT:

Hydrocarbons contain only two elements, which are

…………………………… and

………………………………………….

The general formula of an alkane is

C H Alkanes form a …………………………..………….. series, ie a …………………… of compounds that will ………………… the same way.

Chemistry Topic 7 – Organic Chemistry p 115 - 117

Draw the displayed formula

Methane

Ethane

Propane

Butane

Make a spider diagram to summarise how short hydrocarbons are different to long ones:

short hydrocarbons

.…

less

v…………………. ,

More

v……………

…….

More

f……………………

Lower

b……………

………

p……………

……

More useful

as

f………………

…..

Complete combustion happens when…

The carbon is o……………………………… to form

c……………………….. d………………………………. and

the h.............................. is oxidised to form

w………………………….. .

CH4 + …….. O2 CO2 + 2 H2O

C3H8 + ……… O2 …….. CO2 + …….. H2O

Fractional distillation is used to

s………………………………………………. hydrocarbon

f………………………… from the mixture in c…………………..

o…………….. . The oil is h………………………….. so that it

v…………………………. .The g…………………….. rise up the

c………………………………… , cooling down as they go. They

c…………………………………… back to l…………………………. when

they reach their b……………………… p ………………… .

C5H12 + …….. O2 …….. CO2 + …… H2O

fraction use no of

carbons

tar for road building >40

KEY WORDS:crackingfeedstockcatalyst

thermal decompositiondecolourised

molecular formuladisplayed formula

ASSESSMENT:

Chemistry Topic 7 – Uses of oil, cracking and alkenes p118

Long carbon chains can be broken up by a form of thermal d……………………………………………. called c…………………………….

Catalytic cracking involves h……………………………. the hydrocarbons to v………………………………………. them, then passing the vapour over the c…………………………………………. .

Steam cracking involves simply heating to a very h…………….. t……………………………………………….. .

The point of cracking is to make shorter hydrocarbons out of long ones. This is useful because…

Cracking always makes a shorter alkane and an alkene.

Complete the equations – colour code alkanes and alkenes

C10H22 C8H18 +

C18 H38 C10H22 +

C14H30 C9H20 +

C12H26 C8H18 +

C22H46 C10H22 +

gas used as a ………………

p…………………….. for cars

f……………………… for use in industry

k…………………………. for fuel

d………………………….. fuel

tar for road building

Feedstock for the petrochemical industry is used to

make:

p……………………………………. (plastics and fabrics)

s………………………………. (for dissolving things)

l…………………………………….. (for making

machinery run smoothly)

d………………………………… (for removing grease.

To test whether something is an alkane

or an alkene you add

b………………………….

w…………………….. and shake it. If it is

an a…………………………. then it

d…………………………………… the

bromine water. If it is an

a……………………… then the bromine

water stays bright o…………………….. .

Alkenes have C=C bonds. For example

ethene molecular formula displayed

formula

C H

FOUR Tests for Common Gases

1. Chlorine

Chlorine ________ damp

_________ ________ ,

turning it white.

2. Oxygen

Oxygen gas will

_______________

a ____________

splint

3. Hydrogen

If you hold a

___________

splint at the open

end of a test tube

containing Hydrogen gas, you’ll get a

___________ _____

GCSE Chemistry Revision –Topic 8: Chemical Analysis part 1 (p122-3)

The definition of PURE depends on where you are coming from….

CHEMISTS EVERYONE ELSE

Formulations

Formulation is a POSH WORD for RECIPE, except that the recipe is very precise, so that the STUFF has specific properties for a precise job!

Formulations are used to make:

•

•

•

•

•

•

Could it be true that I hold here, in my mortal hand, a nugget of purest

“green”?

Pure STUFF melts and boils at SPECIFIC

TEMPERATURES. So you can TELL if something

is a ______ _____________ by measuring the

mp or bp and looking it up in a ______ ______ .

Impurities _________ the mp and _________

the bp

4. Carbon Dioxide

Bubbling Carbon Dioxide through an aqueous

solution of ___________ ______________

(known as limewater), causes the solution to turn

________ .

The FORMULATION of Coca-Cola has changed over the years, but it is still an INDUSTRIAL SECRET!

Originally the formulation contained cocaine (which was derived from the coca leaf) and caffeine (which came from the kola nut), leading to the name “Coca-Cola” – the K was replaced cos it looks better!

The Secret Recipe for Coco-Cola’s “Natural Flavourings”Oil Orange 80 ml Oil Lemon 120 mlOil Nutmeg 40 mlOil Cinnamon 40 mlOil Coriander 20 mlOil Neroli 40 mlAlcohol 2 litres (let stand for 24 hours)

Working out what the chemical is

You can calculate a number based on the experiment. It is called the __________ for each chemical

Measure the distance moved by the solvent (A)

Measure the distance moved by the spot (B)

The Rf value is the ratio of these two values

Since (B) must be less than (A), Rf values are ALWAYS less than ONE!

The further the substance moves through the stationary phase, the _________ the Rf value.

GCSE Chemistry Revision –Topic 8: Part 2 – Paper Chromatography (p124-5)

Chromatography uses Two Phases

Chromatography is an analytical method used to

___________ out the substances in a mixture.

Information can be used to __________the

substances.

The two phases are:

A ________ phase, where the molecules CAN

move. It is always a __________ or _______

A ____________ phase, where the molecules

CAN’T move. It can be a ________ or a really

thick ________ .

How it works…..

1. During the experiment the substances in the

sample move between the stationary and mobile

phases, forming an __________ between them.

2. The Mobile phase moves THROUGH the

stationary phase and anything ___________ in

the mobile phase moves with it.

3.The speed at which a chemical moves depends

on the amount of time it spends in the mobile

phase.

4. The more time in the mobile phase, the

__________ it moves.

5. The substance will separate to form _____ .

6. A _______ substance only forms ONE spot

because there is only one substance in it!

Ans

wer

s 1.

D, 2

A, 3

C, 4

0.7

5

KEY WORDS:AlgaeOceansNitrogen

Carbon DioxideOxygen

Atmosphere

Phase 1

The Earth formed ____________ billion years ago.

Initially the first crust formed, which was covered in _________, which gave out a lot of gases, and formed the early ____________.

GCSE Chemistry Revision – Topic 9–atmosphere

Phase 2

How did the oceans form?

What happened to the Carbon Dioxide that dissolved in the oceans?

What do the shells of marine animals contain?

What types of organisms evolved to extract Carbon Dioxide for photosynthesis?

The early atmosphere contained…

•mostly __________________

•virtually no _______________

Volcanic activity also released ________ , ______ _________, and small amounts of ________ and __________.

EXTRA INFORMATIONWhere can we find

evidence for what the old atmosphere was like?

Carbon compounds can be trapped in fossil fuels and rocks.

Explain using simple diagrams how fossil fuels are formed.

GCSE Chemistry Revision – Topic 9- atmosphere

Plants and animals die, and are buried

Compression

Gases and oil trapped under impermeable rock

Give three facts about Limestone.

Phase 3

Green plants and algae producing oxygen

Write the photosynthesis equation that shows how green plants and algae produce oxygen.

True or false

Green plants formed before Algae ( T/ F )

Oxygen allowed more complex life forms to evolve (T / F )

The atmosphere we have today is similar to the atmosphere 200 million years ago ( T / F )

Fill in and label the pie chart showing the current composition of the atmosphere.

KEY WORDS:

AbsorbWavelength

Thermal radiationRe-radiate

Greenhouse effectClimate change

Name these molecules

CO2 (g)

CH4 (g)

H2O (g)

These are …………………………………….

gases : they make the

atmosphere

………………………………………

GCSE Chemistry Revision – Topic 9 – climate change and greenhouse effect p 130-131

radiation Comes from the …

Absorbed by atmosphere?

Short wavelength

Long wavelength

Use the diagram to complete this

Another name for long wave radiation is

…………………….. radiation: this ………………

……….. the surface of the earth. This is called the

……………………… effect.

Explain the effect of these examples of human activity

MORE KEY WORDS:

Peer-reviewReliabilityVariables

BiasComputer model

Explain these effects of climate change

The greenhouse effect is useful because…

KEY WORDS:

Carbon footprint Greenhouse gas Renewable energy

Emissions Carbon capture Life cycle

A carbon footprint is a measure of…

GCSE Chemistry Revision – Topic 9–carbon footprint and pollution 132-134

We could reduce carbon footprints by:

• Using….

instead of…

Individuals could reduce their carbon footprint by:

1)

2)

3)

Use more e_________ processes to conserve e________ and reduce w ______.

Governments could put c___ on emissions. Companies pay for a l________ for e_________ up to that limit.

Capture c_____ d______ before it is released into the atmosphere. It would be stored in…

Governments could tax companies or individuals based on…

Examples include…

Making reductions to carbon footprints is difficult because..

New technologies are

not yet well developed

Carbon footprints are difficult to measure because…

You would need to consider the following factors to make a rough calculation of the carbon footprint of a service, p_________ or e________:•

•

•

•

Particulates

Particulates in the air cause lots of problems .

If Inhaled:

For the environment:

Combustion

What is combustion?

What is a hydrocarbon?

Complete combustion is when…

The products of complete combustion are…

Incomplete combustion is when…

The products of complete combustion are…

GCSE Chemistry Revision – Topic 9–carbon footprint and pollution 132-134

Sulfur Dioxide and Oxides of Nitrogen

Sulfur dioxide is released during the combustion of...

Nitrogen oxides are created from…

When these gases mix with _________ in clouds they form dilute ________ _____ or dilute _________ ______. This falls as ________ _______.

Acid rain is bad because it…

You can test for sulfur impurities in a fuel by bubbling combustion gases through _________ _________ solution. If SO2 is present the indicator will turn _____ in colour indicating an ______ pH.

Complete the diagram above showing formation of acid rain by filling in the blank boxes

KEY WORDS:complete combustion hydrocarbonincomplete combustion particulatesglobal dimming sulfur dioxideacid rain oxides of nitrogen

Carbon monoxide

Why is carbon monoxide so dangerous?

How does it stop your blood from doing it’s job?

What are the effects of carbon monoxide poisoning on humans?

Why is carbon monoxide so hard to detect?