Menu
Print
Name
Date
Class
CHAPTER 11 REVIEW
Molecular Composition of Gases
MIXED REVIEW
SHORT ANSWER
1.
The average speed of a gas molecule is most directly related to the
(a)
(b)
(c)
(d)
2.
Answer the following questions in the space provided.
.
polarity of the molecule
pressure of the gas
temperature of the gas
number of moles in the sample
Which of the following statements best represents Graham’s law for two gases at the same
temperature?
(a)
(b)
(c)
(d)
The molar masses and the velocities are inversely proportional.
The molar masses and the velocities are directly proportional.
The molar masses and the square roots of the velocities are directly proportional.
The molar masses and the squares of the velocities are inversely proportional.
3. Water is synthesized from its elements according to the following equation:
2H2(g) O2(g) → 2H2O(l)
a. Which is greater, the volume of H2 consumed or the volume of
O2 consumed?
b. Which is greater, the mass of H2 consumed or the mass of O2
consumed?
4. Consider a 2.24 L sample of an ideal gas at STP.
a. How many moles are present in the sample, or is more data needed?
b. How many molecules are present in the sample, or is more data
needed?
c. What is the mass of the sample, or is more data needed?
PROBLEMS
provided.
Write the answer on the line to the left. Show all your work in the space
5.
Calculate the volume of 3.5 mol of an ideal gas at 24°C and 760 torr.
MODERN CHEMISTRY
HRW material copyrighted under notice appearing earlier in this work.
CHAPTER 11 MIXED REVIEW
97
Menu
Print
Name
Date
Class
MIXED REVIEW continued
6.
What is the molar mass of a gas that has a density of 2.68 g/L at STP?
7. A sample of oxygen gas has a mass of 8.00 g. Its boiling point is 183°C.
a. What is the boiling point in kelvins?
b. What is the formula and molar mass of oxygen?
c. How many moles of oxygen are present in the 8.0 g sample?
d. What pressure does the sample exert if it is placed in a rigid 8.21 L bottle
at 77°C?
8. Hydrogen gas can be collected in the laboratory by adding an acid to aluminum metal according to
the following equation:
2Al(s) 6HCl(aq) → 2AlCl3(aq) 3H2(g)
a. Determine the volume of H2 that forms at 20°C and a barometric
pressure of 750. torr when 9.00 g of aluminum react according to the
above equation.
b. Typically, hydrogen gas is collected by water displacement. Recalculate
the volume of the dry gas taking into account the partial pressure of water
vapor at the reaction temperature.
98
CHAPTER 11 MIXED REVIEW
MODERN CHEMISTRY
HRW material copyrighted under notice appearing earlier in this work.
Menu
Print
Name
Date
Class
CHAPTER 11 REVIEW
Molecular Composition of Gases
MIXED REVIEW
SHORT ANSWER
1.
c
The average speed of a gas molecule is most directly related to the
(a)
(b)
(c)
(d)
2.
Answer the following questions in the space provided.
d
.
polarity of the molecule
pressure of the gas
temperature of the gas
number of moles in the sample
Which of the following statements best represents Graham’s law for two gases at the same
temperature?
(a)
(b)
(c)
(d)
The molar masses and the velocities are inversely proportional.
The molar masses and the velocities are directly proportional.
The molar masses and the square roots of the velocities are directly proportional.
The molar masses and the squares of the velocities are inversely proportional.
3. Water is synthesized from its elements according to the following equation:
2H2(g) O2(g) → 2H2O(l)
volume of H2
a. Which is greater, the volume of H2 consumed or the volume of
O2 consumed?
mass of O2
b. Which is greater, the mass of H2 consumed or the mass of O2
consumed?
4. Consider a 2.24 L sample of an ideal gas at STP.
0.100 mol
a. How many moles are present in the sample, or is more data needed?
6.0 1022 molecules b. How many molecules are present in the sample, or is more data
needed?
more data is needed
PROBLEMS
provided.
5.
c. What is the mass of the sample, or is more data needed?
Write the answer on the line to the left. Show all your work in the space
85 L
Calculate the volume of 3.5 mol of an ideal gas at 24°C and 760 torr.
MODERN CHEMISTRY
HRW material copyrighted under notice appearing earlier in this work.
CHAPTER 11 MIXED REVIEW
97
Menu
Print
Name
Date
Class
MIXED REVIEW continued
6.
60.0 g/mol
What is the molar mass of a gas that has a density of 2.68 g/L at STP?
7. A sample of oxygen gas has a mass of 8.00 g. Its boiling point is 183°C.
90 K
a. What is the boiling point in kelvins?
O2; 32.00 g/mol b. What is the formula and molar mass of oxygen?
0.25 mol
c. How many moles of oxygen are present in the 8.0 g sample?
0.80 atm
d. What pressure does the sample exert if it is placed in a rigid 8.21 L bottle
at 77°C?
8. Hydrogen gas can be collected in the laboratory by adding an acid to aluminum metal according to
the following equation:
2Al(s) 6HCl(aq) → 2AlCl3(aq) 3H2(g)
98
12.2 L
a. Determine the volume of H2 that forms at 20°C and a barometric
pressure of 750. torr when 9.00 g of aluminum react according to the
above equation.
12.5 L
b. Typically, hydrogen gas is collected by water displacement. Recalculate
the volume of the dry gas taking into account the partial pressure of water
vapor at the reaction temperature.
CHAPTER 11 MIXED REVIEW
MODERN CHEMISTRY
HRW material copyrighted under notice appearing earlier in this work.