# 5522.5523 APChemistry Summer Work 2011 by xiuliliaofz

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```									AP Chemistry Summer Work

By knowing this material you have a jump start on the year, and we will have more time to spend
on new concepts. This will allow you to devote more time to learning the new material and
therefore learn it better.

This summer assignment is strongly recommended. We will have quizzes over this material
during the first week of classes. You need to pass the quizzes. No pressure!  Email me, Mr. Burke, at
kburke@susd.org, if you have questions. I will be visiting family for a couple weeks in June and a week
in July, but I will check my email regularly.

The following topics will be on the quizzes in the first unit:
Naming: Know how to name a compound from its formula and how to write a formula from the name.
Compounds you need to be able to name include ionic compounds (with transition metals and polyatomic
ions), binary molecules, and acids

A guide for how to name compounds is given at the end of the assignment. (p.4-5)

Important Ideas
 Definitions of element, atom, molecule, compound, matter, substance, mixture
 States of matter
 SI units for: volume, length, mass, energy, temperature
 Units for: density, molarity, molar mass
 Conversion between Kelvin and Celsius
 Significant figures: for multiplication and division; for addition and subtraction
The rules for sig. figs are given at the end of this assignment. (p.6)

Basic atomic structure:
 Electrons, protons, and neutrons – their charges and where they are found in the atom
 Mass number, atomic number, avg. atomic mass/molar mass – what each means and how you
would find the value for them
 Ions and isotopes – know what they are
 How to find the number of electrons, protons, and neutrons

Electron Structure
 Pauli exclusion principle, Aufbau principle, and Hund’s rule
 Electron configurations
 Quantum numbers

Bonding
 The three types of bonds: covalent, ionic, and metallic.
 Know what differentiates the 3 types of bonds from each other, the types of elements in each, and
what the electrons do in each.

Stoichiometry: Everybody’s favorite pastime!
 Know how to convert between centimeters, millimeters, kilometers, nanometers, and meters.
 Know how to change units using dimensional analysis. I.e. miles/hour into m/s
 1 mol = 6.02x1023 particles = the molar mass of a substance
 Calculate the percent composition by dividing the part by the whole.
 Calculate empirical formulas by finding the # of moles of each element and comparing the ratios
between them.

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AP Chemistry Summer Work

   Calculate molecular formulas by finding the ratio between the empirical molar mass and the
molecular molar mass.
   Know how to figure out which reactant is used up first during a reaction. It’s called the limiting
reagent or limiting reactant. Find the number of moles of each reactant and compare the ratio
between them to the ratios in the balanced chemical equation. OR Find the amount of product
each of the reactants could make if it’s completely used up and the smallest one wins.

That should be more than enough, right? Not letting your brain go completely to mush over the
summer is not a terrible thing. Remember to email me if you have questions.

You may find it helpful to visit this webpage: http://ex.susd.org/cbrandt. Highly recommended
is the “Honors and AP Chemistry” and “internet Chemistry resources” sections. The
powerpoint presentations in the AP chem. Section are informative and the Erik’s Chemistry
section under internet chemistry resources is also great.

Here is a sample homework assignment. In years past this would have been required on the
first day of class but this year it will become part of your week one quiz. Forewarned is
forearmed!

1. Give the number of significant digits in the following numbers:
a) 0.005800              c) 1,002,000              e) 1200
b) 1200.                 d) 2.0000                 f) 0.000809

2. Perform the following calculations.
a) 11.08 – 4.714                d) 7.500 x 2.0 x 3.50
b) 8.35 + 4.85                  e) 49.91/5.903/0.0387
c) (34.02—33.84)                f) (5.85 + 7.38) x 4.2200
0.00482

3. Would the following pure substances be held together by ionic, covalent, or metallic bonds?
a) sand, SiO2                    c) lithium chlorate              f) lead acetate
b) bronze                        d) steel                         f) acetic acid

4. What type of bond involves….
a) the transfer of electrons between atoms
b) sharing of electrons between two specific atoms
c) an electrostatic attraction/force between charged particles
d) delocalized sharing of electrons around many cations

5. You are given a bottle that contains 2.36 ml of a yellow liquid. The total mass of the liquid and the
bottle is 5.26 g. The empty bottle weighs 3.01 g. What is the density of the liquid?

6. An 8.47 g sample of a solid is placed in a 25.00 ml flask. The remaining volume of the flask is filled
with benzene (The solid is not soluble in benzene.). The solid and the benzene together weigh 24.54
g. The density of benzene is 0.879 g/ml. What is the density of the solid?

7. Gold is alloyed (mixed) with other metals to increase its hardness when making jewelry.

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AP Chemistry Summer Work

Consider a piece of gold jewelry that weighs 9.85 g and has a volume of 0.675 cm3. The jewelry
contains only gold and silver, which have densities of 19.3 g/cm3 and 10.5 g/cm3, respectively.
Assuming the total volume of the jewelry is the sum of the volumes of the gold and silver that it
contains, calculate the percentage of gold (by mass) in the jewelry.

8. A bar of pure gold has a mass of 4.5 kg. How many atoms of gold are in the bar?

9.                         Sn + Ag2SO4  Sn(SO4)2 + Ag
a)   What is the charge on the tin in Sn(SO4)2?
b)   Balance the reaction.
c)   Label the products and reactants.
d)   How many mols of silver will be produced if 3.00 mol of tin react?
e)   What is the limiting reactant if 2.3 g of tin react with 5.4 g of silver sulfate?
f)   What mass of silver can be produced from the reaction in part (e)?

10. Give the electron configuration for
a) neutral cobalt
b) cobalt (II) ion
c) cobalt (III) ion

11. Give the quantum numbers for each of the valence electrons in arsenic.

12.    Name each of the following compounds.                  13. Write the formulas for these compounds.
a. MgI2                                               a. Zinc oxide
b. Na2S                                               b. Aluminum iodide
c. PCl3                                               c. dinitrogen monoxide
d. SiF4                                               d. sulfur trioxide
e. FeBr2                                              e. nitric acid
f. CoS                                                f. sodium carbonate
g. H2SO3                                              g. lithium phosphate
h. Na2CO3                                             h. cobalt (II) nitrate
i. NH4NO3                                             i. potassium iodide
j. Ba3(PO4)2                                          j. sodium nitride
k. MgI2                                               k. dinitrogen pentoxide
l. CCl4                                               l. lead (IV) oxide
m. HClO3                                              m. hydrocyanic acid
n. CoS                                                n. aluminum sulfide
o. Cu2S                                               o. copper (I) hydroxide
p. B2O3                                               p. hydrobromic acid
q. Mg3(PO4)2                                          q. phosphorus trichloride
r. CrCO3                                              r. disulfur dichloride
s. N2O                                                s. ammonium sulfate
t. BaF2                                               t. calcium chloride
u. HBr                                                u. silicon tetrafluoride

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AP Chemistry Summer Work

Reference material that may be helpful.
Nomenclature and Formulas:

Acids-- The compound is an acid when the cation is hydrogen.
If the anion ends in -ide, then add hydro- before the name of the halogen and change the ending to
-ic. HI is hydroiodic acid.
If the anion is a polyatomic ion ending in -ate, only change the suffix to -ic. i.e. H2CO3 is carbonic acid.
If the anion is a polyatomic ion ending in –ite, change the suffix to –ous. i.e. HClO2 is chlorous acid.
Note: “Acid” following the name shows that the cation is hydrogen.

Molecular Compounds-- made of non-metals which are covalently bonded together. Over the centuries, many
covalent molecules have been given multiple common and scientific names. For simplicity and uniformity, a
system of prefixes has been developed.
Prefix             Number of atoms
mono-                      1 -- only used on second element
di-                        2
tri-                       3
tetra-                     4
penta-                     5
hexa-                      6
hepta-                     7
octa-                      8
nona-                      9
deca-                     10
The first element is listed by name with the appropriate prefix, except for mono-.
The second also has the needed prefix but ends with the suffix -ide.
N2O dinitrogen monoxide.
PCl3 phosphorus trichloride.
Charges are NOT used in determining the name or the formula because the bonds are covalent.

Organic Compounds-- carbon-based molecular compounds use a different system than the rest of the covalent
molecules.
The nomenclature for these molecules will formally covered in an organic unit during the year.

Ionic Compounds-- made up of a positive ion and a negative ion. The positive ion is almost always
a metal (except NH4+), and the negative is either a non-metal ion or a polyatomic ion.
The total positive charge must equal the total negative charge.

Metal with non-metal-- The name of the metal comes first, followed by the non-metal whose
ending changes to -ide. [Oxygen becomes oxide; boron becomes boride.]
The number of atoms does not need to be stated because it is determined by
the charge.
AlCl3 is aluminum chloride.

Transition Metals-- The metals in this block do always lose the same number of electrons
when they ionize. Therefore, the charge they carry must be stated in the name to
signify what the formula will be.
Pb can have a 4+ or a 2+ charge.
Lead oxide then could be either PbO2 or PbO.
Then names must be written as lead (IV) oxide and lead (II) oxide to distinguish between the two.
The charge is always written in parenthesis after the name of the metal.
*If only the formula is given, the charge on the transition metal can be determined
from the charge on the anion.

Note: Two transition metal exceptions-- Zn is always 2+; Ag is always 1+

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AP Chemistry Summer Work

Charges are NOT written for them.
Two exceptions which aren’t transition metals-- Pb can be 4+ or 2+; Sn can be 4+ or 2+
Polyatomic ions-- Ions made up of more than one element covalently bonded together.
Positive :        ammonium        NH4+
Negative:
1-                                 2-                        phosphate         PO43-
-                              2-
acetate           C2H3O2            carbonate         CO3
cyanide           CN-               chromate          CrO42-
hydroxide         OH  -             dichromate        Cr2O72-
nitrate           NO3   -           sulfate           SO42-
permanganate MnO4         -         peroxide          O22-
chlorate          ClO3-
3-

You can think of the bold face as the base names. When the ion is changed you can change the name
accordingly. [Or you can simply memorize them all.]
O       If the number of oxygens decreases, the ending changes from -ate to -ite.
SO42- becomes SO32-, the name is sulfite.

If the number of oxygens drops to only one, add the prefix hypo- .
ClO- is hypochlorite.

ClO4- is perchlorate

Note: When the number of O is changes, the charge remains the same!

H        If you add one hydrogen, you put the word hydrogen or the prefix bi- before the name of the ion.
HCO3- is either hydrogen carbonate or bicarbonate.

If you add two hydrogens, put dihydrogen before the name of the ion.
H2PO4- is dihydrogen phosphate

Note: Adding hydrogen (H+) is the same as adding a positive charge, so the total charge on
the polyatomic ion also changes.

** You will need to either memorize the boldface ions and the rules to go with their changes or to
memorize all of them. Pick which is easier for you.

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AP Summer Course Curriculum

Rules for Significant Digits:

Significant figures are critical when reporting scientific data because they give the reader an idea of how
well you could actually measure/report your data. Before looking at a few examples, let's summarize the
rules for significant figures.
1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant.
2) ALL zeroes between non-zero numbers are ALWAYS significant.
3) ALL zeroes which are SIMULTANEOUSLY to the right of the decimal point AND at the end
of the number are ALWAYS significant.
4) ALL zeroes which are to the left of a written decimal point and are in a number >= 10 are
ALWAYS significant.

A helpful way to check rules 3 and 4 is to write the number in scientific notation. If you must get rid
of the zeroes, then they are NOT significant.

Here’s another way to look at the same rules:

1.   Zeroes in the beginning of a number never count.
2.   Zeroes at the end of a number count only if there is a written decimal point.
3.   The digits 1 - 9 always count.
4.   Zeroes between the digits 1 - 9 always count.

Using Significant Digits in calculations

There are two basic rules when using significant digits in calculations. The first is that when adding or
subtracting, the answer can only be as precise as the least precise number used. For example, a 250
pound person who has a hair pulled out (say, 0.001 pounds) still weighs 250 pounds. That's because the
last significant digit is the 5 (in the tens place), and everything after that is not even estimated. So you
have no idea how many ones of pounds the guy weighs, or how many tenths, or hundredths, or
thousandths. Therefore, you have no idea what from to subtract 0.001 pounds. So he still weighs 250
pounds.

The other rule is that when multiplying or dividing, the answer has the same number of significant digits
as the number used with the least. For instance, there is a quick estimation of pi (π) as 22/7. On a
calculator, that gives 3.1428571423, which is pretty close. But if you had measured a circle as 22 feet
around and 7 feet across, the answer must be rounded to "3" to match the least number of significant
digits.

Other Hints
Every measurement and calculation using measurements should take significant figures into account.
Exceptions are counting numbers (like dividing by 20 students to get a class average) and exact
equivalents (like 1000 mm = 1 m, which is perfect and exact by definition).

Here's another way to think of significant digits: when you write a number in scientific notation, all the
zeroes that are un-necessary for precision disappear, and the remaining digits are significant. 510 become
5.1x102 (2 sig figs) and 510.0 becomes 5.100x102 (still 4 sig figs). The exponent part isn't significant
because it takes over for the place-holding zeroes. For that reason, only the decimal part if pH or similar

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AP Summer Course Curriculum

values count as significant figures; the number before the decimal is the exponent (look up pH in a
chemistry text and logarithm in a math book).

You can also start memorizing these Ions, Common Charges, Element Symbols, Solubility, and
Strong Acids and Bases: (These will be on quizzes throughout first semester and possibly into
second semester, but not on the ones you must pass at the beginning of the year.)
Ions: Know the names and formulas (including charges) for the following ions:
Sulfate        SO42-           Dihydrogen phosphate             Chlorite      ClO2-
Sulfite        SO32-                H2PO4-                      Chlorate      ClO3-
2-
Hydrogen sulfate               Oxalate          C2O4            Perchlorate   ClO4-
-                        -
(bisulfate) HSO4             Acetate C2H3O2                   Bromate       BrO3-
-                              -
Nitrate        NO3             Hydroxide        OH              Iodate        IO3-
-                              -
Nitrite        NO2             Cyanide          CN              Permanganate MnO4-
3-                                2-
Phosphate      PO4             Carbonate        CO3             Chromate      CrO42-
Hydrogen phosphate HPO42-      Bicarbonate      HCO3-           Dichromate    Cr2O72-
-
Hypochlorite OCl                 Ammonium      NH4+

Common charges for:
Alkali metals                       Ferrous (Iron II)                   Chromium
Alkaline earth metals               Cupric   (Copper II)                Zinc
Halogens                            Cuprous (Copper I)                  Silver
Oxygen and sulfur                   Stannic   (Tin IV)                  Mercury (Hg22+ & Hg2+)
Nitrogen                            Stannous (Tin II)                   Manganese
Ferric (Iron III)                   Plumbous (Lead II)

Solubility:
Soluble compounds contain:               Exceptions
NO3-                             none
C2H3O2-                          none
Cl-, Br-, I-                     salts with Ag+, Hg+, Pb2+
SO42-                            salts with Ca2+, Sr2+, Ba2+, Hg+, Pb2+

Insoluble compounds contain: Exceptions
S2-                          salts with NH4+, alkali metal cations, and Ca2+, Sr2+, Ba2+
2-
CO3                          salts with NH4+, the alkali metal cations
2-
PO4                          salts with NH4+, the alkali metal cations
-
OH                           salts with alkali metal cations and Ca2+, Sr2+, Ba2+

Strong acids
Sulfuric, nitric, hydrochloric, hydrobromic, hydroiodic, perchloric, chloric,

Strong bases
Alkali metal hydroxides and Ca(OH)2, Sr(OH)2, Ba(OH)2, CaO and Na2O

Elements— Know both the names and symbols for:
Hydrogen, lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium,
cobalt, zinc, molybdenum, tungsten, platinum, gold, mercury, silver, cadmium, boron, aluminum,
gallium, carbon, silicon, germanium, tin, lead, nitrogen, phosphorus, arsenic, antimony, bismuth,

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AP Summer Course Curriculum

oxygen, sulfur, selenium, fluorine, chlorine, bromine, iodine, helium, neon, argon, krypton,