Question

On heating a flask, at constant pressure, from $27\%$ to ${227}^{o}C,200mL$ of air was expelled out .what was the volume of the flask?

• A. 0.02 L
• B. 0.06 L
• C. 0.04 L
• D. 0.3 L

Answer 1

The correct option is D 0.3 L

Solution:-

According to Charle's law

$V\propto T$

$\frac{V_1}{V_2}=\frac{T_1}{T_2}$

Let the initial volume be V.

$\therefore$ Final volume, $\left(V_2\right)=?$

Initial temperature, $\left(T_1\right)=27℃=(273+27)K=300K$

Final temperature, $\left(T_2\right)=227℃=(227+273)K=500K$

$\frac{V}{V_2}=\frac{300}{500}$

$\Rightarrow V_2=\frac{5}{3}V$

Amount expelled = 200 mL

As we know that,

amount expelled $=V_2-V_1$

$\therefore \frac{5}{3}V-V=200$

$\Rightarrow \frac{2}{3}V=200$

$\Rightarrow V=300mL=0.3L$

Hence, the volume of the flask was 0.3 L