Semester 2 Exam Review
Honors Chemistry/Langellier
Chapters Covered:
Chapter 5 (naming,
formula writing) to a lesser
extent, as used in writing
products for equations, net
ionic equations
Ch. 8 (Stoichimetry, incl.
LR, % yield)
Ch. 15 (Covalent cmpds,
properties, Lewis sketches,
polarity)
Name
Period
1
3
Date
Ch. 6 (Mol conversions
from grams, volume of
gas @ STP; EF and MF)
Ch. 7 (Rxns, balancing and type,
predicting products, net ionic
equations)
Ch. 11 (Gases/gas laws)
Ch. 14 (ionic cmpnds, properties
and formulas)
Our combination
solutions/molarity/solubility unit..
We did less with this, so won’t be
as heavily weighted.
Chapter 5
1. How can you tell whether a compound is ionic, covalent, or an acid by looking at its
formula?
* ID each as an acid, an ionic compound, or a molecular compound. Name each.
KCl Na2SO4
NO2
HCl SF6
Pb(NO3)2
H3PO4
PCl3
2. Realize that ionic formulas are written in the ratio of ions such that total net charge = zero.
Be able to write ionic formulas.
*For each element given, write the charge of the ion each would make. Then write the
formula of the compound that each pairing of ions would make. (Be able to perform
the same task using polyatomic ions.) Then, name each compound.
S
N
Cl
Na
Al
Ca
3. Know naming rules/prefixes for naming covalent cmpds.
* Name the following: CS2 N2O4 IBr
* Write formulas for: Arsenic trichloride
Xenon tetrafluoride
4. Know naming rules for naming binary acids and ternary acids.
* Name these: HBr HNO3 HI H2CO3
* Write formulas for: Hydrosulfuric acid
Sulfuric acid
Chapter 6
5. Be able to find the molar mass of any given compound.
* CH3Cl
Pb(NO3)4
CuSO4•5H2O
Silicon dioxide
6. Be able to find the % composition by mass for each element in a given formula.
* Find % comp for each element in KMnO4, find % water in MgSO4•7H2O
Know all the appropriate conversion factors, and be able to convert between mass, moles, L
of gas @STP, and particles (atoms, molecules) according to the master chart:
*How many grams are in 4.5 moles of NaCl? How many atoms are in 456 g of gold?
*How many moles are in 45.2 L of nitrogen gas at STP? How many grams N2 is that? How
many molecules N2 is that?
7. Know what an empirical formula is, what a molecular formula is, and the relationship
between them.
* Write whether each is a MF or EF. If it’s a MF, write its EF:
H2O H2O2 KMnO4
K2C2O4
C6H12O6
Al(ClO3)3
8. Be able to find an EF, given % composition (or a MF, given % comp and molar mass).
* What is the EF of a compound made of 68.32% Pb, 10.57% S, and 21.10% O?
* What is the MF of a compound made of 82.66% C and 17.34% H, if it has a molar
mass of 58.12 g/mol?
Ch. 7
9. Know the vocabulary and symbols surrounding chemical equations, including (but not
limited to) products, reactants, the symbols for solids, liquids, gases, and aqueous; yield,
precipitate
10. Be able to balance a given equation correctly:
* AgNO3 (aq) + Cu (s)  Cu(NO3)2 (aq) + Ag (s)
* AgNO3 (aq) + K2CrO4 (aq)  KNO3 (aq) + Ag2CrO4 (s)
* Mg (s) + O2 (g)  MgO (s)
* C6H12O6 (s) + O2 (g)  CO2 + H2O
* (NH4)2Cr2O7 (s)  N2 (g) + H2O (g) + Cr2O3 (s)
11. Be able to ID any reation as combustion, decomposition, single replacement, double
replacement, or combination.
* Do so for the above 5 reactions.
Ch. 8
12. Have a verbal plan to do stoichiometry problems. Use units to guide your work.
For example: How many grams of calcium will react exactly with 45.0g of sulfur
according to the reaction Ca + S  CaS?
My thoughts: OK. Is the equation balanced? Yes, so no need to do it. Alright, I’ll need to
convert the grams of S into moles of S, then use the mole ratio to convert to moles of Ca, then
use Ca’s molar mass to convert to mass of Ca. Let’s do this!
1 mol S
1 mol Ca
40.08 g Ca
45.0 g S 


=
32.07 g S
1 mol S
1 mol Ca

* Your turn: How many grams of water can be made from 5.44 L of O2 gas at STP?
H2 + O2  H2O
* How many atoms of gold are needed to make 123 g of AuCl3?
Au + Cl2  AuCl3
13. Be able to do LR problems.
* using the last equation, what mass of gold (III) chloride can be made from 100.0 g of
gold and 75.0 g of chlorine gas?
14. Be able to use a stoich problem to find % yield.
* If in the example above, 58.9 g of AuCl3 is recovered, what is % yield?
15. Don’t get goofed if the problem is easier than the hardest kinds:
* Using the equation H2 + O2  H2O,
a) how many moles of oxygen gas react to form 7.8 moles of H2O?
b) how many grams of hydrogen gas are needed to make 55.8 moles of water?
Ch. 11
16. Know the gas laws, and be able to perform calculations based on them.
* If 6.5 L of helium at 744 mmHg is compressed to 1.2 L at constant temperature, what
is its new pressure?
* If 54.3 L of xenon gas at 45°C is heated to 654°C at constant pressure, what is its new
volume?
* If 452 L of argon gas at 895 K and 6.5 atm is changed to conditions of 205 K and 1.1
atm, what is its new volume?
* At what temperature will 54.6 g of neon occupy a volume of 87 L at standard
pressure?
17. Know the relationships (direct or inverse) of pairs of gas variables (n, P, V, or T)
17½ . Be able to use/apply Dalton’s Law, in general or in a “collected over water” type
problem.
 If the total pressure of a mixture of gases A, B, and C is 845 mmHg, and PA = 350.
mmHg, PB = 250. mmHg, what is the partial pressure of gas C?
 If the room pressure is 749 mmHg, what is the number of moles of hydrogen gas that
have been collected if the volume of collected gas is 1.5 L at a temperature of 25°C?
(The vapor pressure of water at 25°C is 24 mmHg)
Ch. 14
18. Know how cations and anions are made. Know how ionic bonds are made. Be able to
write electron configurations for cations and anions.
* Compared to the fluorine atom, has the fluoride ion gained or lost electrons? Write the
electron configuration of each to show this. Do the same for the sodium atom/sodium ion.
19. Be able to determine the number of valence electrons for any atom in the s or p blocks.
Be able to sketch the dot diagrams to show this number of valence electrons.
* How many valence electrons for each? Mg O P Xe Na Ga Br Si
* Sketch dot diagrams for each of the above.
20. Know how an ionic bond is formed. Be able to predict formula of ionic compounds.
21. Know how “sea of electrons” allows metals to conduct electricity well.
22. Know the properties of ionic compounds as shown in table 15.5 in book.
Ch. 15
19. Know how covalent bonds are formed. Know the details of the composition of single,
double, and triple covalent bonds.
20. Be able to sketch Lewis structures for simple molecules. Be able to judge a Lewis
structure for its accuracy.
* Sketch Lewis structures for the following: SO2 H2O CCl4 NF3 [NO3]-1 SiO2
* Are the following Lewis structures correct? Draw them correctly if they
are incorrect.

:S H H


:OO:
QuickTime™ and a
TIF F (Uncompressed) decompressor
are needed to see this picture.
21. For a given Lewis structure (or one you’ve drawn), be able to determine the shape of the
molecule, and the hybridization of any atom on the molecule by inspection.
*For each correctly sketched molecule in the above two problems, name the shape of
the molecule and the hybridization of the central atom.
22. Be able to identify molecules which can have resonance structures by inspecting Lewis
structures.
*Do so for the above molecules.
23. Know bond angles for the various shapes as predicted by VSEPR.
* What is the bond angle about the central atom in a molecule whose shape is
a) linear
b) bent (sp3)
c) trigonal planar
d) trigonal pyramid e) tetrahedral
24. Know what makes bonds polar, and be able to predict if a bond is polar.
* Who’s polar, who’s nonpolar?
H–H H–Cl I–Cl O=O
25. Know how to use Lewis sketches/shapes/bond polarities to predict if a molecule is polar.
* Label as polar or nonpolar molecules: H2O NH3 CH4 CO2 O3
Ch. 17 (Solutions and intro to acid-base)
27.Know what solubility is, be able to use a solubility graph to determine information about
the solubility of various salts.
28. Be able to predict whether a given solution is saturated, unsaturated, or supersaturated
using the graph.
29. Be able to calculate molarity of a solution, or use volume and molarity of a solution to
determine the moles (or mass) of solute present.
30. Be comfortable with the terms solute, solvent, solution.
This review is meant to stimulate you to think about the topics that our final exam focus on.
It is probable that the test will contain questions that are not directly covered on this review
sheet. Let your study time take you back into your notes from the year and back to your
textbook; allow yourself to think about more than just the problems you see on this review.