Question

A $2.24L$ cylinder of oxygen at NTP is found to develop a leakage. When the leakage was plugged the pressure dropped to 570mm of Hg. The number of moles of gas that escaped will be:

• A. $0.0233$
• B. $0.050$
• C. $0.075$
• D. $0.09$

Answer 1

The correct option is A $0.0233$

Number of moles of oxygen gas present initially at $NTP$

$n_1=\frac{PV}{RT}=\frac{1\times 2.24}{0.0821\times 293}=0.093mol$

Number of moles of oxygen gas present finally at NTP

$n_2=\frac{PV}{RT}=\frac{\frac{570}{760}\times 2.24}{0.0821\times 293}=0.0698mol$

Moles of gas escaped = $n_2-n_1$
$=0.023$ moles

So, the correct option is $A$