Question

What volume will be occupied by 11.7 g of Helium in a balloon at an altitude of 10.0 km if the air pressure is 0.262 atm and the temperature is -50.0 °C?

Answer 1

Answer: 204 L

Explanation:

According to ideal gas equation:

$PV=nRT$

P = pressure of gas = 0.262 atm

V = Volume of gas = ?

n = number of moles = $\frac{\text {given mass}}{\text {molar mass}}=\frac{11.7g}{4g/mol}=2.92$

R = gas constant =$0.0821Latm/Kmol$

T =temperature =$-50^0C=(273+(-50))K=223K$

$V=\frac{nRT}{P}$

$V=\frac{2.92\times 0.0820 L atm/K mol\times 223K}{0.262atm}=204L$

Thus volume occupied by 11.7 g of Helium in a balloon is 204L