Question

gas laws fact sheet
ideal gas law pv = nrt
ideal gas constant r = 8.314 $\frac{l kpa}{mol k}$ or r = 0.0821 $\frac{l atm}{mol k}$
standard atmospheric pressure 1 atm = 101.3 kpa
celsius to kelvin conversion k = °c + 273.15
7
select the correct answer
a volleyball is full of pressurized air. the air temperature is 24.6°c. the volleyballs absolute pressure is 130.75 kilopascals, and its volume is 5.27 liters. how many moles of air are inside the volleyball?
a. 0.278 mol
b. 3.37 mol
c. 3.59 mol
d. 25.2 mol
e. 28.0 mol

Explanation:

Step1: Convert temperature to Kelvin

$T = 24.6+273.15=297.75\ K$

Step2: Rearrange ideal - gas law for $n$

$n=\frac{PV}{RT}$

Step3: Substitute values

$P = 130.75\ kPa$, $V = 5.27\ L$, $R = 8.314\frac{L\ kPa}{mol\ K}$, $T = 297.75\ K$
$n=\frac{130.75\times5.27}{8.314\times297.75}$
$n=\frac{689.0525}{2476.4745}\approx 0.278\ mol$

Answer:

A. 0.278 mol