Question

If the pressure of gas contained in a closed vessel is increased by 0.4% when heated by 1 degree C its initial temperature must be _____

• A. $20K$
• B. $250K$
• C. ${25}^{o}C$
• D. $300K$

Answer 1

Answer: (B)

$250K$

$PV=nRT$ .....(i)

$P(1+\frac{0.4}{100})V=nRT(T+1)$ ....(ii)

eqn. (ii) divided by (i)

$1+\frac{0.4}{100}=\frac{T+1}{T}=1+\frac{1}{T}$

$T=\frac{100}{0.4}=250K$

Hence, the correct option is $\text{B}$