1. No category

REVIEW FOR CHEM 1405: TEST #4
b 3.
Which Lewis Dot Formula below is incorrect?
(a) Cl
d 4.
(c) Ga
(d)
S
(e) Cl
(b)
I
(c) C
N
(e) Al
(d)
(b) 6
(c) 3
(d) 5
(e) 4
(b) 6
(c) 3
(d) 5
(e) 4
How many unpaired electrons are shown in a Lewis Dot Formula for silicon?
(a) 0
b 9.
(b) Sr
How many valence electrons does a Iodine atom have?
(a) 7
c 8.
(e) Li
How many valence electrons does a phosphorus atom have?
(a) 2
a 7.
(d) Br
Which Lewis Dot Formula below is incorrect?
(a) Ca
d 6.
(c) C
Which Lewis Dot Formula is incorrect?
(a) Na
c *5.
(b) B
(b) 1
(c) 2
(d) 3
(e) 4
Below are some elements with their number of valence electrons. Which is incorrect?
(a) Ca – 2
(b) Cl – 5
(c) K – 1
(d) B – 3
(e) O – 6
c *10. An atom of which element below has the most unpaired electrons?
(a) Ba
(b) Al
(c) P
(d) F
(e) O
Boyle’s Law: The Volume-Pressure Relationship
b 12. The statement "At constant temperature, the volume occupied by a definite mass of a gas
is inversely proportional to the applied pressure." is a statement of _______ Law.
(a) Charles's
(d) Avogadro's
(b) Boyle's
e) Gay-Lussac's
(c) Graham's
e 14.
A sample of oxygen occupies 47.2 liters under a pressure of 1240. torr at 25°C. What
volume would it occupy at 25°C if the pressure were decreased to 730. torr?
(a) 27.8 L
(b) 29.3 L
(c) 32.3 L
(d) 47.8 L
(e) 80.2 L
b 15. A gas occupies 1.75 liters and exerts a pressure of 730. torr at a certain temperature. If the
temperature is held constant, what volume must it occupy to exert a pressure of 820. torr?
(a) 0.641 L
(b) 1.56 L
(c) 3.44 L
(d) 0.291 L
(e) 1.08 L
b 16. Ammonia, NH3, is used to as fertilizer and as a refrigerant. What is the new pressure if
25.0 g of ammonia with a volume of 750 mL at 1.50 atm is expanded to 7.50 L at
constant temperature?
(a) 15 atm
e 17.
(b) 114 mm Hg
(c) 0.15 psi
(d) 6.67 atm
(e) 15 mm Hg
The volume of a sample of a gas is 405 mL at 10.0 atm and 467 K. What volume will it
occupy at 4.29 atm and the same temperature?
(a) 17.4 L
(b) 189 mL
(c) 174 mL
(d) 1047 mL (e) 944 mL
c*18. A 5.00-L sample of a gas exerts a pressure of 1040. torr at 50.0°C. In what volume would
the same sample exert a pressure of 1.00 atm at 50.0°C?
(a) 0.146 L
(b) 3.65 L
(c) 6.84 L
(d) 8.72 L
(e) 5.20 L
e*19. A sample of oxygen occupies 47.2 liters under a pressure of 1240. torr at 25°C. By what
percent does the volume of this sample change if the pressure were decreased to 730. torr
at 25°C?
(a) 37.8%
(b) 41.1%
(c) 43.4%
(d) 46.1%
(e) 69.9%
d 20. A sample of gas occupies a volume of 1.60 L at a pressure of 720. torr. What would be
the pressure of this gas if it were compressed to 1.20 L at the same temperature?
(a) 540. torr
c 21.
(c) 180. torr
(d) 960. torr
(e) 1440 torr
A sample of carbon monoxide, CO, occupies a volume of 350. mL and exerts a pressure
of 1020. torr at 25°C. If the volume expands to 500. mL with no temperature change,
what pressure will the gas exert?
(a) 617 torr
a 22.
(b) 360. torr
(b) 827 torr
(c) 714 torr
(d) 938 torr
(e) 1457 torr
A 6.25-L sample of gas exerts a pressure of 1.46 atm at 25°C. What would be the
pressure of this gas sample at 25°C if it were compressed to a volume of 5.05 L?
(a) 1.81 atm
(b) 1.18 atm
(c) 21.6 atm
(d) 1.70 atm
(e) 0.280 atm
d 23. The volume of a gas sample is 600. mL at 25°C and a pressure of 2.04 atm . What would
be the pressure of this sample if it were allowed to expand to 850. mL at 25°C?
(a) 2.89 atm
(b) 3.10 atm
(c) 4.40 atm
(d) 1.44 atm
(e) 0.346 atm
Charles’s Law: The Volume-Temperature Relationship;
the Absolute Temperature Scale
a 24.
The statement "At constant pressure, the volume occupied by a definite mass of a gas is
directly proportional to the absolute temperature." is a statement of _______ Law.
(a) Charles's
(d) Avogadro's
c 25.
(b) Boyle's
(e) Gay-Lussac's
(c) Graham's
If the volume of a sample of Ar gas is tripled while pressure is held constant, what
happens to the absolute temperature?
(a) It remains constant.
(d) It increases nine-fold.
(b) It decreases to 1/3.
(e) It decreases to 1/6.
(c) It triples.
b 27. A gas sample occupies 4.20 L under a pressure of 800. torr at 350. K. At what
temperature will it occupy 3.60 L at the same pressure?
(a) 7 K
(b) 300. K
(c) 408 K
(d) 300.°C
(e) 770. K
d 28. A temperature of 316.23oC is equivalent to:
(a) 43.08oK
(d) 589.38 K
c 30.
(b) 143.08 K
(e) none of these
(c) 689.38oK
Radon is a radioactive gas found below ground. If a sample of radon occupies 29 mL at
25 oC, what volume will it occupy at 500 K? Assume constant pressure.
(a) 5140 mL
(b) 29 mL
(c) 49 mL
(d) 17 mL
(e) 500 mL
d 31. A sample of nitrogen occupies 5.50 liters under a pressure of 900. torr at 25.0°C. At what
temperature will it occupy 10.0 liters at the same pressure?
(a) 32°C
(b) –109°C
(c) 154°C
(d) 269°C
(e) 370.°C
b 32. A given mass of xenon gas has a volume of 200. mL at 25.0°C and 760. torr. To what
temperature must the xenon be heated to occupy 450. mL at 760. torr?
(a) 376°C
(b) 398°C
(c) 416°C
(d) 512°C
(e) 492°C
a 33.
Ethylene, C2H4, is used to make plastic milk bottles. When the volume of 1000 g of
ethylene at 25oC is decreased from 40.0 L to 15.0 L, what is the new temperature
assuming the pressure is held constant?
(a) 112 K
c 34.
(b) 410 K
(c) 25 oC
(d) 522 oC
(e) 795 K
A sample of a gas occupies 460. mL at 70.0°C and 1.00 atmosphere. At what temperature
would the gas occupy 650. mL at the same pressure?
(a) 154°C
(b) –30.3°C (c) 212°C
(d) 101°C
(e) 188°C
d 35. A 300. mL sample of neon is confined under a pressure of 0.420 atm at 15.0°C. At what
temperature would it occupy 1.00 L at the same pressure?
(a) –187°C
e 36.
(e) 960.°C
(b) 16.5 L
(c) 2.75 L
(d) 3.67 L
(e) 8.25 L
(b) 10.1 %
(c) 7.1 %
(d) 21 %
(e) 1.2 %
The temperature of a fixed amount of hydrogen gas is reduced from 20.0°C to –20.0°C at
constant pressure. If the original volume of gas is 420. mL, what is the final volume?
(a) 466 mL
e 39.
(d) 687°C
Snoopy is inflated for the Macy’s Thanksgiving parade with 50,000 L of He at 25 oC and
1.2 atm. What is the percent decrease in Snoopy’s volume if the temperature drops to
4 oC before the parade? Assume constant pressure.
(a) 7.58 %
c 38.
(c) 380.°C
If 5.50 L of argon gas at 273°C is heated at constant pressure to a temperature of 546°C,
what would be its new volume?
(a) 11.0 L
c 37.
(b) 86.4°C
(b) 257 mL
(c) 363 mL
(d) 406 mL
(e) 392 mL
Suppose you inhaled 1.00 liter of air at –30.0°C (–22°F), and held this air long enough to
heat it to body temperature, 37.0°C. What would be the new volume of the air in the
lungs assuming constant pressure?
(a) 0.972 L
(b) 0.811 L
(c) 1.23 L
(d) 1.02 L
(e) 1.28 L
d 40. 2.00 g of fluorine occupies 1.18 L at STP. What volume will it occupy at –14oC and
1 atm?
(a) 1.20 L
e 41.
(b) 2.73 L
(c) 5.89 L
(d) 1.12 L
(e) 6.20 L
A gas sample occupies 1.00 L at 120.°C and 1.00 atm. What volume will it occupy at
STP?
(a) 1.14 L
e 42.
(c) 0.846 L
(d) 0.782 L
(e) 0.695 L
A gaseous sample has a volume of 3.88 L at 115°C and 760. torr. What would be its
volume at STP?
(a) 5.51 L
a 43.
(b) 1.44 L
(b) 2.98 L
(c) 3.63 L
(d) 3.37 L
(e) 2.73 L
A sample of He gas has a volume of 373 mL at 0.0°C and 825 torr. What would be its
volume at STP?
(a) 405 mL
(b) 508 mL
(c) 344 mL
(d) 235 mL
(e) 1680 mL
b 44. By international agreement the standard temperature and pressure (STP) for gases is
(a) 25°C and one atmosphere.
(c) 298.15 K and 760. torr.
(e) 293 K and one atmosphere.
e 45.
(b) 273.15 K and 760. torr.
(d) 0°C and 700. torr.
A sample of neon, Ne, occupies 1700. mL at STP. At constant pressure, what temperature
is necessary to increase the volume to 2100. mL?
(a) –14°C
(b) –52°C
(c) 32°C
(d) 52°C
(e) 64°C
b 46. A sample of gas occupies 650. mL at STP. If the pressure remains constant, what volume
will it occupy at a temperature of 65.0°C?
(a) 776 mL
(b) 805 mL
(c) 487 mL
(d) 525 mL
(e) 910. mL
d 47. A sample of helium occupies 5.00 L at STP. What volume will the sample occupy at
0.0°C and 890. torr?
(a) 3.56 L
(b) 3.72 L
(c) 4.06 L
(d) 4.27 L
(e) 5.86 L
2) Assuming similar conditions, how many liters of chlorine gas react to produce 2 L of
hydrogen chloride gas?
H2(g) + Cl2(g) → 2 HCl(g)
A) 1 L
B) 2 L
C) 3 L
D) 4 L
E) none of the above
Answer: A
Section: 9.1 Interpreting a Chemical Equation
3) How many moles of carbon monoxide react with 1 mol of oxygen gas according to the
balanced chemical equation?
2 CO(g) + O2(g)
2 CO2(g)
A) 1 mol
B) 2 mol
C) 3 mol
D) 4 mol
E) none of the above
Answer: B
Section: 9.1 Interpreting a Chemical Equation
4) Assuming similar conditions, how many liters of carbon monoxide gas react to produce 2 L of
carbon dioxide gas?
2 CO(g) + O2(g)
2 CO2(g)
A) 1 L
B) 2 L
C) 3 L
D) 4 L
E) none of the above
Answer: B
Section: 9.1 Interpreting a Chemical Equation
5) How many moles of steam, H2O, react with 1 mol of charcoal, C, according to the balanced
chemical equation?
C(s) + H2O(g)
CO(g) + H2(g)
A) 1 mol
B) 2 mol
C) 3 mol
D) 4 mol
E) none of the above
Answer: A
Section: 9.1 Interpreting a Chemical Equation
6) Assuming similar conditions, how many liters of steam, H2O, react to produce 1 L of
hydrogen gas?
C(s) + H2O(g)
CO(g) + H2(g)
A) 1 L
B) 2 L
C) 3 L
D) 4 L
E) none of the above
Answer: A
Section: 9.1 Interpreting a Chemical Equation
13) How many moles of iodine vapor react with 1.00 mol of hydrogen gas?
__H2(g) + __I2(g)
__HI(g)
A) 0.500 mol
B) 1.00 mol
C) 2.00 mol
D) 4.00 mol
E) none of the above
Answer: B
Section: 9.2 Mole-Mole Relationships
14) How many moles of hydrogen iodide are produced from 1.00 mol of iodine?
__H2(g) + __I2(g)
__HI(g)
A) 0.500 mol
B) 1.00 mol
C) 2.00 mol
D) 4.00 mol
E) none of the above
Answer: C
Section: 9.2 Mole-Mole Relationships
15) How many moles of hydrogen gas react to yield 1.00 mol of hydrogen iodide?
__H2(g) + __I2(g)
__HI(g)
A) 0.500 mol
B) 1.00 mol
C) 2.00 mol
D) 4.00 mol
E) none of the above
Answer: A
Section: 9.2 Mole-Mole Relationships
16) How many moles of water are produced from 1.00 mol of hydrogen peroxide?
__H2O2(l)
__H2O(l) + __O2(g)
A) 0.500 mol
B) 1.00 mol
C) 2.00 mol
D) 4.00 mol
E) none of the above
Answer: B
Section: 9.2 Mole-Mole Relationships
17) How many moles of oxygen are produced from 1.00 mol of hydrogen peroxide?
__H2O2(l)
__H2O(l) + __O2(g)
A) 0.500 mol
B) 1.00 mol
C) 2.00 mol
D) 4.00 mol
E) none of the above
Answer: B
Section: 9.2 Mole-Mole Relationships
61) What is the volume of oxygen gas at STP from the decomposition of 10.8 g of mercuric
oxide (216.59 g/mol)?
__HgO(s)
__Hg(l) + __O2(g)
A) 0.558 L
B) 1.12 L
C) 2.23 L
D) 52.2 L
E) 209 L
Answer: A
Section: 9.5 Mass-Volume Problems
62) What is the mass of mercuric oxide (216.59 g/mol) that decomposes to release 0.750L of
oxygen gas at STP?
__HgO(s)
__Hg(l) + __O2(g)
A) 0.0388 g
B) 0.155 g
C) 3.63 g
D) 7.25 g
E) 14.5 g
Answer: E
Section: 9.5 Mass-Volume Problems
63) What is the volume of oxygen gas at STP from the decomposition of 1.70 g of sodium nitrate
(85.00 g/mol)?
__NaNO3(s)
__NaNO2(s) + __O2(g)
A) 0.224 L
B) 0.448 L
C) 0.896 L
D) 3.23 L
E) 12.9 L
Answer: A
Section: 9.5 Mass-Volume Problems
64) What is the mass of sodium nitrate (85.00 g/mol) that decomposes to release 2.55 L of
oxygen gas at STP?
__NaNO3(s)
__NaNO2(s) + __O2(g)
A) 0.336 g
B) 1.34 g
C) 4.84 g
D) 9.68 g
E) 19.4 g
Answer: E
Section: 9.5 Mass-Volume Problems
65) What is the volume of oxygen gas at STP from the decomposition of 9.57 g of silver chlorate
(191.32 g/mol)?
__AgClO3(s) → __AgCl(s) + __O2(g)
A) 0.560 L
B) 0.747 L
C) 1.12 L
D) 1.68 L
E) 3.36 L
Answer: D
Section: 9.5 Mass-Volume Problems