Question

A sample of gas has a pressure of 21 Pa at 30degF. What would its pressure be at 80degF? The volume of the gas remains constant.

Answer 1

23 Pa

Explanation:

According to ideal gas law, PV = nRT. If V is constant, then:

P/T = P/T

Remember that P and T are absolute. So °F must be converted to either Rankine or Kelvin.

To convert °F to Rankine, add 459.67.

30°F + 459.67 = 489.67 R

80°F + 459.67 = 539.67 R

21 Pa / 489.67 R = P / 539.67 R

P = 23.1 Pa

Rounded to two significant figures, the pressure is 23 Pa.