An open flask containing air is heated from `300K` to `500K`. What percentage of air will be escaped to the atmosphere, if the pressure is kept constant ?

Options

A. 80
B. 40
C. 60
D. 20

Answer

b

Explanation

(b) `V_(1)=V, T_(1)=300K, T_(2)=500K,V_(2)=?`
At constant pressure `V_(1)T_(2)=V_(2)T_(1)`
`:. " "V_(2)=(V_(1)T_(2))/(T_(1))=(Vxx500)/(300)=(5V)/(3)`
`:.` volume of air escaped
=final volume - initial volume
`(5V)/(3)-V=(2V)/(3)`
`:.` % of air escaped `=(2V//3)/(5V//3)xx100=40"%"`