Question

A stationary cylinder of oxygen used in a hospital has the following characteristics at room temperature $300K$, gauge pressure $1.38\times {10}^{7}Pa$, volume $16L$. If the flow rate, measured at atmospheric pressure, is constant at $2.4L/min$, the cylinder will last for nearly

• A. $5h$
• B. $10h$
• C. $15h$
• D. $20h$

Answer 1

The correct option is C $15h$

Assuming the total time to empty the cylinder is $t$
$V_2=2.4\times t$
Applying Ideal gas equation
$\frac{P_1{V}_1}{T_1}$ = $\frac{P_2{V}_2}{T_2}$
$\frac{1.38\times {10}^7\times 16}{300}$ = $\frac{{10}^5\times 2.4\times t}{300}$
$t=920min$
$t=15h$