combined gas laws

Question

1.A sample of hydrogen gas occupies a volume of 6.95 L at 54.0°C and 0.700 atm.

If it is desired to increase the volume of the gas sample to 9.61 L, while decreasing its pressure to 0.435 atm, the temperature of the gas sample at the new volume and pressure must be ________°C.

2.A sample of hydrogen gas occupies a volume of 9.49 L at 65.0°C and 378 torr.

If the volume of the gas sample is increased to 11.6 L, while its temperature is increased to 128.0°C, the resulting gas pressure will be_________ torr.

Answer 1

Combined gas law: P1V1/T1 = P2V2/T2

P1 = 0.700 atm .................................... P2 = 0.435 atm

V1 = 6.95 L ......................................... V2 = 9.61 L

T1 = 54.0ºC + 273 = 327K ....................T2 = ?

Plug these values into the combined gas law equation and solve for T2. Subtract 273 to get the answer in ºC

Do #2 in a similar fashion solving for P2