Question

A sample of gas at 25°C has a volume of 11 L and exerts a pressure of 0.868 atm. How many moles

Answer 1

Answer: The number of moles of gas present are 0.390 moles

Explanation:

To calculate the number of moles of gas, we use the equation given by ideal gas which follows:

$PV=nRT$

where,

P = pressure of the gas = 0.868 atm

V = Volume of the gas = 11 L

T = Temperature of the gas = $25^oC=[25+273]K=298K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles of gas = ?

Putting values in above equation, we get:

$0.868atm\times 11L=n\times 0.0821\text{ L. atm }mol^{-1}K^{-1}\times 298K\\\\n=\frac{0.868\times 11}{0.0821\times 298}=0.390mol$

Hence, the number of moles of gas present are 0.390 moles