Chem 31
Chabot College
Fall 2015
Dr. Stanton
Exam 1 Review Sheet
Introduction (First Day Lecture and Chapter 3)
Terms: atoms, chemical bonds, molecules, elements, compounds, mixtures
gases, liquids, solids (including pictures at the particulate level)
electrical charges, ions
Scientific Method: observation, generalization (Law), hypothesis, experiment, theory
Conservation of Mass, Conservation of Energy
nanoscale, macroscale
Chapter 2--Calculations
scientific notation
significant figures
significant figures in arithmetic
rule for addition/subtraction, rule for multiplication/division
rounding
metric system
m, g, L
nano-, milli-, centi-, kilo- (MEMORIZE these prefixes)
dimensional analysis
conversions with square and cubed units
density
temperature conversions: Celsius, Kelvin
Chapter 4--Nuclear Model of the Atom, Periodic Table
nuclear model of the atom, Rutherford's scattering experiment
electrons, protons, neutrons
amu
isotopes
calculating average atomic mass
nuclear symbols; determining number of protons and neutrons
periodic table
groups (families), periods
Chapter 5--Chemical Formulas
first 20 elements (MEMORIZE)
ionic charge for groups IA, IIA, IIIA, VIA, VIIA
chemical formulas for ionic compounds
polyatomic ions: MEMORIZE ion formulas and names
NO3-, SO42-, CO32-, PO43-, NH4+, OHcovalent compounds: MEMORIZE formulas and names
CO, CO2, NH3, H2O
seven diatomics MEMORIZE H2, N2, O2, F2, Cl2, Br2, I2
Chapter 6--The Mole
calculate molar mass
percentage composition
converting gmole, moleg, gmolecules etc.
Lab
Appropriate significant figures for various measuring devices
(ruler marked in millimeters, graduated cylinder marked in tenths of milliliters, etc.)
Chemistry 31
Name _________________
Exam 1
Closed book, closed notes. Show all work (no work, no credit.) Please turn your cell phone ALL
the way off. Use the back of the periodic table as your scratch paper.
1 inch = 2.54 cm
1 ton = 907 kg
Density of steel: 7.8 g/cm3
23
NAv = 6.02 x 10
density of gasoline: 0.703 g/mL
3
1 cm = 1 mL
1 gallon = 3.785 L
density = mass/volume
1. (9 points) Significant figures:
15.8  13
3.52 x 105

18.63 - 17.1 =
2
19.5
8.7222 x 10
2. (6 points) Write the correct name:
Si_________________________
Mg_________________________
B _________________________
Write the correct symbol:
potassium__________
phosphorus__________
fluorine__________
3. (16 points) Chemical formulas:
Name
Formula
Name
Formula
lithium nitrate
nitrogen
ammonium sulfide
aluminum sulfate
calcium hydroxide
barium carbonate
(barium = Ba)
ammonia
sodium phosphate
4. (12 points)
a) Calculate the molar mass of sodium sulfate.
b) Suppose I have 0.381g of carbon dioxide. How many moles is this? How many molecules?
5. (9 points) Butadiene (C4H6) is an example of a molecule longer than it is wide (general shape,
).
Suppose I have a box containing five butadiene molecules. Show what the box contents will
look like in the solid, liquid, and gas phase.
Solid
Liquid
Gas
6. (9 points)
a) Fill in the blanks in the following chart (make sure the symbol includes the mass number and
the charge, if there is one):
Symbol
81
Number of
protons
Number of
neutrons
42
55
Number of
electrons
Charge
Br 0
Mass
(amu)
7. (4 points)
State the group and period for each atom:
Atom
Group
C
Ca
Period
8. (9 points) In 1954, U.S. steel mills produced 120 million tons of steel, enough to give each man,
woman and child in the U.S. a cube of steel 17 inches on each side.
17 inches
17 inches
What is the mass (in kg) of this cube of steel 17 inches on each side?
17 inches
9. (12 points) Suppose I drive my car 12,000 miles each year, and my car get 32 miles per gallon.
a) How many liters of gas will I use in a year?
b) How many grams of gasoline will I use?
10. (10 points) Short Answer
a) What is a hypothesis?
b) 539.3 L = ___________ mL
c) 9382.3 cm = _____________km
Number of Significant
Figures
0.0059003
Number
Figures
1.5 x 1010
of
Significant
11. (4 points) For each picture, label with all of the appropriate labels. You should include one label
from the list of first column labels and as many labels from the second column labels as
appropriate. Write the labels inside the boxes. The triangles represent one kind of atom, and the
circles a different kind of atom.
First Column Labels
Second Column Labels
a) element
S) solid
b) compound
L) liquid
c) mixture
G) gas