Gas Law Problems- Combined Gas Law

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Abbreviations				Conversions
atm - atmosphere			K  =  °C  +  273
mm Hg - millimeters of mercury		1 cm3 (cubic centimeter)  =  1 mL (milliliter)
torr - another name for mm Hg		1 dm3 (cubic decimeter)  =  1 L (liter)  =  1000 mL
Pa - Pascal (kPa  =  kilo Pascal)	Standard Conditions
K - Kelvin				0.00 °C  =  273 K
°C - degrees Celsius			1.00 atm  =  760.0 mm Hg  =  101.325 kPa  =  101,325 Pa

Most of the answers

73. A gas has a volume of 800.0 mL at minus 23.00 °C and 300.0 torr. What would the volume of the gas be at 227.0 °C and 600.0 torr of pressure?

74. 500.0 liters of a gas are prepared at 700.0 mm Hg and 200.0 °C. The gas is placed into a tank under high pressure. When the tank cools to 20.0 °C, the pressure of the gas is 30.0 atm. What is the volume of the gas?

75. What is the final volume of a 400.0 mL gas sample that is subjected to a temperature change from 22.0 °C to 30.0 °C and a pressure change from 760.0 mm Hg to 360.0 mm Hg?

76. What is the volume of gas at 2.00 atm and 200.0 K if its original volume was 300.0 L at 0.250 atm and 400.0 K.

77. At conditions of 785.0 torr of pressure and 15.0 °C temperature, a gas occupies a volume of 45.5 mL. What will be the volume of the same gas at 745.0 torr and 30.0 °C?

78. A gas occupies a volume of 34.2 mL at a temperature of 15.0 °C and a pressure of 800.0 torr. What will be the volume of this gas at standard conditions?

79. The volume of a gas originally at standard temperature and pressure was recorded as 488.8 mL. What volume would the same gas occupy when subjected to a pressure of 100.0 atm and temperature of minus 245.0 °C?

80. At a pressure of 780.0 mm Hg and 24.2 °C, a certain gas has a volume of 350.0 mL. What will be the volume of this gas under STP

81. A gas sample occupies 3.25 liters at 24.5 °C and 1825 mm Hg. Determine the temperature at which the gas will occupy 4250 mL at 1.50 atm.

82. If 10.0 liters of oxygen at STP are heated to 512 °C, what will be the new volume of gas if the pressure is also increased to 1520.0 mm of mercury?

83. What is the volume at STP of 720.0 mL of a gas collected at 20.0 °C and 3.00 atm pressure?

84. 2.00 liters of hydrogen, originally at 25.0 °C and 750.0 mm of mercury, are heated until a volume of 20.0 liters and a pressure of 3.50 atmospheres is reached. What is the new temperature?

85. A gas balloon has a volume of 106.0 liters when the temperature is 45.0 °C and the pressure is 740.0 mm of mercury. What will its volume be at 20.0 °C and 780 .0 mm of mercury pressure?

86. If the absolute temperature of a given quantity of gas is doubled and the pressure tripled, what happens to the volume of the gas?

87. 73.0 mL of nitrogen at STP is heated to 80.0 °C and the volume increase to 4.53 L. What is the new pressure?

88. 500.0 mL of a gas was collected at 20.0 °C and 720.0 mm Hg. What is its volume at STP?

89. A sample of gas occupies 50.0 L at 15.0 °C and 640.0 mm Hg pressure. What is the volume at STP?

90. A gas is heated from 263.0 K to 298.0 K and the volume is increased from 24.0 liters to 35.0 liters by moving a large piston within a cylinder. If the original pressure was 1.00 atm, what would the final pressure be?

91. The pressure of a gas is reduced from 1200.0 mm Hg to 850.0 mm Hg as the volume of its container is increased by moving a piston from 85.0 mL to 350.0 mL. What would the final temperature be if the original temperature was 90.0 °C?

92. If a gas is heated from 298.0 K to 398.0 K and the pressure is increased from 2.230 x 103 mm Hg to 4.560 x 103 mm Hg what final volume would result if the volume is allowed to change from an initial volume of 60.0 liters?

Combined Gas Law which requires Dalton's Law also

IMPORTANT NOTE: A gas collected over water is always considered to be saturated with water vapor. The vapor pressure of water varies with temperature and must be looked up in a reference source.

93. 690.0 mL of oxygen are collected over water at 26.0 °C and a total pressure of 725.0 mm of mercury. What is the volume of dry oxygen at 52.0 °C and 800.0 mm pressure?

94. 400.0 mL of hydrogen are collected over water at 18.0 °C and a total pressure of 740.0 mm of mercury.

a) What is the partial pressure of H2?
b) What is the partial pressure of H2O?
c) What is the volume of DRY hydrogen at STP?

95. 45.0 mL of wet argon gas is collected at 729.3 mm Hg and 25.0 °C. What would be the volume of this dry gas at standard conditions?

96. 19.1 L of He gas is collected over water at 681.3 mm Hg and 18.5 °C. What would be the volume of this dry gas at standard conditions?

97. 407 mL of H2 gas is collected over water at 785.3 mm Hg and 23.5 °C. What would be the volume of this dry gas at standard conditions?

98. 93.0 mL of O2 gas is collected over water at 0.930 atm and 10.0 °C. What would be the volume of this dry gas at standard conditions?

99. 6.12 L of wet xenon gas is collected at 2.00 x 105 Pa and 80.0 °C. What would be the volume of this dry gas at standard conditions?

100. A sample of oxygen collected over water when the atmospheric pressure was 1.002 atm and the room temperature, 25.5 °C occupied 105.8 mL. What would be the volume of this dry gas at standard conditions?

101. 1.000 L of hydrogen gas is collected over water at 30.0 °C at a pressure of 831.8 mm Hg. Find the volume of dry hydrogen collected at STP.

102. 50.6 mL of a gas is collected over water at 18.0 °C and 755.5 mm Hg pressure. What is the volume of dry gas at STP?

103. Write the combined gas law in equation form. Solve the combined gas law for V2.


Most of the answers

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