Aflatoxin 1) B1 (C17H12O6) is present in a blue mold that may grow on peanuts and rice
stored improperly in humid conditions. The toxin affects the liver. In people who have
been exposed to hepatitis aflatoxin is thought to be synergistic with the development of
liver cancer. How many molecules are in 10 mg of aflatoxin B1?
2) By chemical analysis, the composition of calcium phosphate is 38.71% calcium,
20.00% phosphorous and 41.29% oxygen. Determine its empirical formula.
3) Balance the following equation and answer the questions below.
A)
FeS2 +
O2
-->
Fe2O3 + SO2
B) If 0.032 moles of FeS2 reacts completely. How many moles of SO2 will
be formed?
4) Which of the following is not a unit-conversion factor for the reaction
2 Al(OH)3 + 3 H2SO4 --->
a.
b.
c.
d.
Al2(SO4)3 + 3 H2O ?
3 mol H2SO4 / 1 mol Al2(SO4)3
1 mol Al2(SO4)3 / 2 mol Al(OH)3
3 mol H2SO4 / 2 mole H2O
2 mol Al(OH)3 / 3 mol H2SO4
5) Consider the reaction below. Which statement correctly identifies the type of
reaction that is occurring?
MnO4- + 8 H+ + 5 e- ---> Mn2+ + 4 H2O
a)
b)
c)
d)
e)
The reaction is an example of a combustion.
MnO4- is undergoing an oxidation.
MnO4- is undergoing a reduction.
The reaction is an example of a dehydrogenation.
The reaction is not a balanced half-reaction.
6) Write the balanced equation for the complete combustion of D-mannoheptulose
(C7H14O7) which is found in the fruit of the avocado tree.
7) A sample of gas has a volume of 505 mL at a pressure of 705 torr. What volume will
the gas occupy at the same temperature but at 755 torr?
8) A mixture is made up of helium, nitrogen and oxygen. Their partial pressures are 311
torr, 0.200 atm, and 0.500 atm respectively. Calculate the total pressure of the mixture in
atm.
9) How does temperature affect the solubility of gases in a liquid? Consider the
solubility of a gas in water. What happens to the solubility as the temperature increases?
A) the solubility of the gas increases.
B) the solubility of the gas decreases.
C) the solubility of the gas remains constant
D) cannot be determined without additional information.
10) As the pressure of a gas at 760 torr is changed to 380 torr at constant temperature,
the of volume the gas:
a) increases
b) decreases
c) remaines the same
d) cannot be determined
11) If the pressure of a sample of gas at 298 K is tripled, what will the new temperature
be when the volume is kept constant?
12) Inhaled air contains O2 at a pressure of 160 torr. The capacity of a human lung is
about 3.00 L. Body temperature is 37.0 oC. Calculate the mass of O2 in a lung after
inspiration.
13) A 1.00 L sample of gas at 27.0 oC is heated so that it expands at constant pressure to
a final volume of 1.50 L Calculate its final temperature.
14) If one serving of cake contains 10.0 mg of cholesterol, which is 0.0259 mmol, what
is the formula mass in g/mol?
15) Which of the following reaction systems tends to become less random as reactants
form products?
A) I2 (s) + Cl2 (g) --> 2 ICl (g)
B) 2 Mg (s) + O2 (g) --> 2 MgO (s)
C) C (s) + O2 (g) --> CO2 (g)
D) S (s) + O2 (g) --> SO2 (g)
16) Explain why CCl4 and C3H8 would or would not form a solution.
17) Water can be made to boil at 90oC by :
A) decreasing the pressure with volume constant
B) increasing the pressure with volume constant
C) increasing the pressure while decreasing the volume
D) decreasing the volume with pressure constant
18) Choose the correct sequence for arranging the following molecules in order of
increasing boiling points:
I. CH4
II. H2O
III. NH3
A)
B)
C)
D)
E)
II < I < III
I < III < II
II < III < I
I < II < III
none of the above
19) Which one or more of the following interactions occur between molecules of
hydrogen (H2)
A) ionic interactions
B) London Dispersion forces
C) Dipole-dipole interactions
D) Hydrogen bonds
20) Molecules with large dipole moments are likely to:
A) have lower melting points than molecules with no dipole moment
B) have higher boiling points than molecules with no dipole moment
C) exist as gases
D) have high vapor pressures
21) For a liquid at its normal boiling temperature, which of the following vapor
pressures is correct?
A) 1 atm
B) 2 atm
C) 273 atm
D) 760 atm
22) Solid sodium chloride has a melting point of 800 oC. This solid is an example of a:
A)
B)
C)
D)
covalent crystal
molecular crystal
ionic crystal
amorphous solid