Question

A 0.100 mile sample of gas is at a temperature of 85.0 degrees C and a volume of 3.47 L. What is the pressure of the gas( in mm hg?)

Answer 1

Answer: 64.6 mmHg

Explanation:

Given that:

Volume of gas V = 3.47L

(since 1 liter = 1dm3

3.47L = 3.47dm3)

Temperature T = 85.0°C

Convert Celsius to Kelvin

(85.0°C + 273 = 358K)

Pressure P = ?

Number of moles of gas N = 0.100 mole

Note that Molar gas constant R is a constant with a value of 0.0082 ATM dm3 K-1 mol-1

Then, apply ideal gas equation

pV = nRT

p x 3.47dm3 = 0.10 x (0.0082 atm dm3 K-1 mol-1 x 358K)

p x 3.47dm3 = 0.29 atm dm3

p = (0.29 atm dm3 / 3.47 dm3)

p = 0.085 atm

Recall that pressure of the gas is required in mm hg, so convert 0.085 atm to mm Hg

If 1 atm = 760 mm Hg

0.085atm = 0.085 x 760

= 64.6 mm Hg

Thus, the pressure of the gas is 64.6 mm hg