Honors Chemistry Name ______
Chapter 13: Gas Laws WS II Date _____/_____/_____ Period _____
This worksheet uses all of the gas laws that we have covered – Boyles, Charles, Dalton’s, Combined, Molar Volume (gas stoichiometry), and Ideal. Provide the formula, plug in values with units, and solve the equation.
1. A 2.00 L sample of a gas originally at 25 degrees C and a pressure of 700. torr is allowed to expand to a
volume of 5.00 L. If the final pressure of the gas is 585 torr, what is its final temperature in Celsius?
P1 = 700. torr
V1 = 2.00 L T2 = T1P2V2 = (298 K)(585 torr)(5.00 L) = 623 K = 350. o C
T1 = 25 oC = 298 K P1V1 (700. Torr)(2.00 L)
P2 = 585 torr
V2 = 5.00 L
T2 = ?
2. A gas has a volume of 350. mL at 740. torr. How many milliliters will the gas occupy at 900. torr if the
temperature remains constant?
P1 = 740. torr
V1 = 350. mL V2 = P1V1 = (740. torr)(350. mL) = 288 mL
P2 = 900. torr P2 (900. torr)
V2 = ?
3.Calculate the number of liters occupied by the following at STP:
a. 0.200 moles of oxygen
0.200 moles O2 / 22.4 L O2 / = 4.48 L O21 mole O2
or PV = nRT or V1 = V2
n1 n2
b. 12.4 grams of chlorine gas
12.4 grams Cl2 / 1 mole Cl2 / 22.4 L Cl2 / = 3.92 L Cl270.90 g Cl2 / 1 mole Cl2
or PV = nRT or V1 = V2
n1 n2
c. a mixture of 0.100 moles of nitrogen gas and 0.500 moles of oxygen gas
0.100 moles N2 gas + 0.500 moles O2 gas = 0.600 moles gas
0.600 moles gas / 22.4 L gas / = 13.4 L gas1 mole gas
or PV = nRT or V1 = V2
n1 n2
4.From the volume, temperature and pressure listed below, calculate the number of moles for the gas:
750.0 cm3 at 27.0 degrees C and 99.0 kPa.
P = 99.0 kPa = 0.977 atm
V = 750.0 cm3 = 750.0 mL = 0.7500 L
n = ? n = PV = (0.977 atm)(0.7500 L)(mole ▪ K)
T = 27.0 oC = 300. K RT (0.0821 L ▪ atm)(300. K)
n = 0.0298 moles
5. A balloon has a volume of 2.0 L indoors at a temperature of 25.0 degrees C. If it is taken outdoors on a
very cold day when the temperature is –28.9 degrees C, what will its volume be in liters? Assume a
constant air pressure within the balloon.
V1 = 2.0 L
T1 = 25.0 oC = 298 K V2 = V1T2 = (2.0 L)(244 K) = 1.6 L
V2 = ? T1 (298 K)
T2 = –28.9 oC = 244 K
6. A gas exerts a pressure of 350.0 torr at 20.0 degrees C. How many torr will it exert if its temperature is
raised to 40.0 degrees C without a change in the volume of the container?
P1 = 350.0 torr
T1 = 20.0 oC = 293 K P2 = P1T2 = (350.0 torr)(313 K) = 374 torr
P2 = ? T1 (293 K)
T2 = 40.0 oC = 313 K
7. If a 0.0500 L sample of gas exerts a pressure of 450.0 torr at 35.0 degrees C, how many milliliters will it
occupy at STP?
P1 = 450.0 torr
V1 = 0.0500 L V2 = P1V1T2 = (450.0 torr)(0.0500 L)(273 K) = 0.0262 L = 26.2 mL
T1 = 35.0 oC = 308 K T1P2 (308 K)(760. torr)
P2 = 760. torr
V2 = ?
T2 = 273 K
8. Calculate the volume of 6.00 g of hydrogen gas at 24.0 degrees C and 1.50 atm.
6.00 g H2 / 1 mole H2 / = 2.97 mole H22.02 g H2
P = 1.50 atm
V = ?
n = 2.97 mole H2 V = nRT = (2.97 mole)(0.0821 L ▪ atm)(297 K)
T = 24.0 oC = 297 K P (mole ▪ K) (1.50 atm)
n = 48.3 L
9. A gas is compressed at constant temperature from a volume of 540. mL to 320. mL. If the initial pressure
was 475 torr, what is the final pressure in atm?
P1 = 475 torr = 0.625 atm
V1 = 540. mL P2 = P1V1 = (0.625 atm)(540. mL) = 1.05 atm
P2 = ? V2 (320. mL)
V2 = 320. mL
10. Calculate the mass of 24.5 mL of SO2 gas at STP.
24.5 mL SO2 / 1 L SO2 / 1 mole SO2 / 64.07 g SO2 / = 0.0701 g SO21000 mL SO2 / 22.4 L SO2 / 1 mole SO2
or PV = nRT then convert moles to grams
11. What is the molecular mass of a gas if 300.0 mL of the gas has a mass of 0.855 g at STP?
P = 1.00 atm
V = 300.00 mL = 0.3000 L
n = ? n = PV = (1.00 atm)(0.3000 L)(mole ▪ K)
T = 273 K RT (0.0821 L ▪ atm)(273 K)
n = 0.0134 mole
0.855 g / = 63.8 g0.0134 mole / mole
or 1 mole = 22.4 L then convert moles to grams
12. A gas has a pressure of 655 torr at 35.0 degrees C. To what Celsius temperature must it be heated to
raise its pressure to 825 torr?
P1 = 655 torr
T1 = 35.0 oC = 308 K T2 = T1P2 = (308 K)(825 torr) = 388 K = 115 oC
P2 = 825 torr P1 (655 torr)
T2 = ?
13. A sample of hydrogen iodide has a mass of 2.28 g and occupies 400.0 mL at STP. What is the molecular
mass of this compound?
400.0 mL / 1 L / 1 mole SO2 / = 0.0179 mole1000 mL / 22.4 L SO2
2.28 g / = 127 g
0.0179 mole / mole
or PV = nRT then 2.28 g / n = molecular mass
14.At what temperature will a gas sample occupy 0.850 L at 1.00 atm pressure if it occupies 400.0 mL at 32.0
degrees C and 1.00 atm?
V1 = 400.0 mL = 0.4000 L T2 = T1V2 = (305 K)(0.850 L) = 648 K
T1 = 32.0 oC = 305 K V1 (0.4000 L)
V2 = 0.850 L
T2 = ?
15. If excess hydrochloric acid is added to 13.5 grams of Al, what volume of hydrogen gas will be produced if
the gas is collected at a temperature of 80.0 degrees C and a pressure of 750. torr?
2 Al + 6 HCl è 2 AlCl3 + 3 H2
13.5 g Al / 1 mole Al / 3 mole H2 / = 0.751 mole H226.98 g Al / 2 mole Al
P = 750. torr = 0.987 atm
V = ?
n = 0.751 mole v = nRT = (0.751 mole)(0.0821 L ▪ atm)(353 K)
T = 80.0 oC = 353 K P (mole ▪ K) (0.987 atm)
n = 22.1 L
16. A container is initially at 0.500 atm and 25 oC. What will the pressure be at 125 oC?
P1 = 0.500 atm
T1 = 25 oC = 298 K P2 = P1T2 = (0.500 atm)(398 K) = 0.668 atm
P2 = ? T1 (298 K)
T2 = 135 oC = 398 K
ANSWERS
1. 350. degrees C 7. 26.2 mL 13. 127 g/mol
2. 288 mL 8. 48.3 L 14. 648 K
3. a. 4.48 Lb. 3.92 L c. 13.4 L 9. 1.05 atm 15. 22.1 L
4. 0.0298 moles 10.0.0701 g 16. 0.668 atm
5. 1.6 L 11.63.8 g/mol
6. 374 torr 12.115 degrees C