MCAS REVIEW DAY 1

MCAS REVIE

W D

AY 1

STUFF

AND A

LCHEMY

Need to add in info on subshells and electron configuration, noble gas configuration

THURSDAY, MAY 31ST (NB PG 43)

Obj: Answer MCAS questions related to Alchemy

Lang. Obj: use correct terms for atoms and the PT

HW: make up work!Announcements:

– Make-up work deadline is Make-up work deadline is Wednesday, June 13Wednesday, June 13thth, 2:00pm, 2:00pm

– Chemistry MCAS is June 5Chemistry MCAS is June 5thth and 6 and 6thth – AP Chemistry forms back ASAP!AP Chemistry forms back ASAP!– Mr. Banks is afterschool today after Mr. Banks is afterschool today after

3 and Monday (no other days next 3 and Monday (no other days next week!)week!)

CHEMCATALYST (NB PG 43)

Answer MCAS questions 1-10 on notebook page 43 (skip the open response)

• note that there are ‘hints’ for some problems

1. C

2. A

3. A

4. B

5. A

6. B

7. B

8. D

9. B

10. C

11.

ANSWER KEY

WHAT WAS DIFFICULT ABOUT THIS?

1. There were a few concepts that we didn’t cover:1.Question 4: releasing heat2.Question 5: percent by mass3.Question 8: oxidation-reduction4.Question 9: buffer solutions5.Question 11: freezing point

“…BUT I’M NOT TAKING THE CHEMISTRY MCAS, WHY DO I HAVE TO REVIEW FOR IT?”Yes, but everyone is taking the City Test, and…

• The City Test, your final exam, is based on the MCAS

• Some questions on the City Test are exactly the same as MCAS

• They cover the same content

TODAY’S AGENDA

1. Answer Practice Questions 1-10 (10 min)

2. Q& A and Answer key (10 min)

3. Alchemy Review (15 min)

4. Selected MCAS Q’s practice (15 min)

5. Answer key, Q&A (5 min)

6. Closing Q (5 min)

ALCHEMY REVIEW

Quick…define matter

NOTES (NB PG 23)

Matter is anything that has mass and volume (takes up space)Energy is the ability to do work or make reactions happen.

What is the difference between mass and volume?

MASS AND VOLUME

• Mass is a measure of the amount of substance. Mass can be measured using an electronic or triple beam balance.

• Volume is the amount of space occupied by an object. The volume of a liquid can be measured in a graduated cylinder.

• Objects with similar volumes can have different masses, and vice versa.

What is the difference between and intensive property and an extensive property?

NOTES (NB PG 31)

Extensive property: A characteristic that is specific to the amount of matter. (ex: size, shape)

Intensive property: A characteristic that does not depend on the size or the amount of matter. (ex: density)

Density: defined as the mass per unit volume (units are usually g/ml = “grams per milliliter”). It is a measure of how much ‘stuff’ is packed into a certain space, where higher density means more stuff packed in

d

m

Vx

What is the difference between a pure substance and a mixture?

Matter

Pure Substances

homogeneouselements

mixture

compounds heterogeneous

made up of atoms made up of atoms

Pure Substances are made of one kind of ‘unit’ that is chemically bonded together

Mixtures are made of many kinds of ‘units’ not chemically bonded together

PURE SUBSTANCES VS. MIXTURES

Can you break down elements under ordinary lab conditions?

ELEMENTS AND MATTER

1. An element is a unique form of matter that serves as a building material for more complex matter.

a) elements cannot be broken apart into two different substances.

b) elements are not destroyed when combined under ordinary lab conditions

2. No matter what was done to the copper, in the end it was back to copper powder.

We can account for all the substances that combined with the copper, thus nothing was ‘created out of nothing’.

3. Law of conservation of mass/matter: The law states that mass/matter cannot be gained or lost in a chemical reaction–matter cannot be created or destroyed.

How is the Periodic Table organized?

PERIODIC TABLE

Mendeleyev organized the periodic table based on the atomic weight and properties of the elements. Mendeleyev’s arrangement of the elements helped to predict the existence of undiscovered elements.

What is the difference between a group and period in the periodic table?

GROUPS AND PERIODS

1. Periodic: occurring or appearing at regular intervals or in regular cycles*

2. Group: a column in the PT

3. Period: a row in the PT

4. Elements in the same group tend to have properties that are:

1. Exactly the same, or2. Change in a regular & predicable way

5. Atomic Weight: the average mass of an atom/element

http://encarta.msn.com

Where are the metals located in the PT? The non-metals?

EXAMPLE:

How did Ernest Rutherford’s gold foil experiment change the model of the atom?

25

1803: “Solid Sphere model”

1. Observed that elements combine in whole number ratios to form compounds2. Matter is not created or destroyed in chemical reactions3. Elements are made of tiny, indivisible particles called atoms

Experiment 1 SummaryJohn Dalton

1897: “Plum Pudding” model

Experiment 2 SummaryJ.J. Thomson

1. most of atom is a positive ‘pudding’2. Has tiny particles with a negative charge

Major changes from the previous model:

Led to

Le

d to

Led to

Led to

1911: Nuclear Model

Experiment 3 SummaryErnest Rutherford

1. Positive area is dense, small, and in the center of the atom2. Electrons circle the nucleus, are tiny and have a negative charge


1918: Proton Model

Experiment 5 SummaryErnest Rutherford


1913: Solar System model

Experiment 4 SummaryNeils Bohr Major changes from

the previous model:

Note: this model should show only protons in the nucleus

Experiment 6 SummaryWerner Heisenberg


Experiment 7 Summary James Chadwick


Leads to ?(New models

will surely come in the

future!?

Led to

Led to

How many protons, neutrons, and electrons are there in one atom of Beryllium-9?

Where is most of its mass located?

element chemical symbol

atomic number

# of protons

# of electrons

# of neutrons

mass number

(P+N)

atomic weight

beryllium 5 9 9.012

fluorine 10

6 12

chlorine 18 35.45

lead 126

potassium 19 39

tin 70

tungsten 184 183.85

29 36

gold 118

Handout #64

Beryllium Atom Fluorine Atom Carbon Atom

Label:Protonsneutronselectrons Nucleus

(hint: see back of pg 56)

Atomic number is the number of protons in the nucleus of an atom.

How many protons and neutrons are there in the following isotope?

Li63

ISOTOPE NOTES (PG 65)

1. Atoms of the same element that have different numbers of neutrons are called isotopes

• same number of protons in the nucleus, just a different number of neutrons

• similar chemical properties• because they have different masses they

MOVE at different rate: Heavier isotopes move slower

Li63

Liab

Atomic numbe

r(P)

Mass #

(P + N)

What particle is ‘ejected’ in alpha decay?

FUSION is the joining of nuclei, FISSION is the splitting apart of a nucleus

How many valence and core electrons are there in an oxygen atom?

VALENCE AND CORE ELECTRONS

How to determine the arrangement of an element’s electrons from the element’s position in the periodic table :1. Atomic number tells you the total number of

electrons2. The period (row #) tells you the number of shells3. The group number (column #) tells you the

number of valence electrons

4. Shells:1. 2e- max2. 8e- max3. 8e- max

WHY does lithium form a +1 ion?

NOBLE GAS ENVY

1. Atoms tend to lose or gain electrons to attain the electron arrangement of the nearest noble gas.

2. When electrons are removed from or added to an atom, the rest of the atom stays the same.1. Protons/neutrons/nucleus

DOES NOT change3. The charge on an ion

is noted with a superscript. O-2

What types of elements form ionic compounds?

DISCUSSION NOTES (NB PG 91)

1. Metal and nonmetal elements combine to form ionic compounds.

2. The electron arrangements of the cations and anions resemble the arrangements of a noble gas atom.

3. The rule of zero charge can be used to determine the chemical formulas of ionic compounds.

Rule of zero charge: In an ionic compound, the positive charges on the metal cations and the negative charges on the nonmetal anions sum to 0. (PG term)

4. Valence electrons in ionic compound generally totals 8 or a multiple of 8 (16, 24, 32…)

What type of bonding does water (H2O) have?

What 3 things can you do to increase the rate (speed) at which a sugar cube dissolves in water?

CLASS WRITES THE NOTES (NB PG 105)WHAT DID WE LEARN ABOUT HOW TO INCREASE THE

RATE OF DISSOLVING A CUBE OF SUGAR?

PRACTICE, PART 2

CLOSING QUESTION

ANSWER KEY

2. C

8. C

18. D

31. C

32. B
































































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MCAS REVIEW DAY 1