Question # A flask containing air (open to the atmosphere) is heated from ( 300 mathrm{K} ) to ( 500 mathrm{K} ). The percentage of air

# A flask containing air (open to the atmosphere) is heated from ( 300 mathrm{K} ) to ( 500 mathrm{K} ). The percentage of air

escaped to the atmosphere is

(a) 16.6

(b) 40

(c) 60

(d) 20

Solution

( operatorname{}^{} quad v_{1}=v )

( T=300 k )

[

v_{2}=? quad T_{2}=500 mathrm{k}

]

From Ideal gas eqt"

[

begin{array}{l}

frac{V_{1}}{T_{1}}=frac{V_{2}}{T_{2}}=frac{V}{300}=frac{V_{2}}{500}

=frac{590 mathrm{V}}{368}=V_{2}=frac{5}{3} mathrm{V}

V_{2}=frac{5}{3} mathrm{V}

end{array}

]

So lrolume excaped ( =V_{f}-V_{i} )

[

=frac{5}{8} V-v=frac{5 v-3 v}{3}

]

[

=frac{2 V}{3}

]

of of are escaped ( =frac{2 v}{3} times 100 times frac{3}{5} )

[

=100 times frac{2}{5}=40 %

]

So option (2) is correct