Question

At ${27}^{o}C$, $1$ atm pressure, density of a gas is $d$. AT constant $P$ at what $T$ its density is $0.75d$?

• A. ${20}^{o}k$
• B. ${30}^{o}C$
• C. ${400}^{o}k$
• D. ${300}^{o}C$

Answer 1

The correct option is C ${400}^{o}k$

At constant P, $d\propto \frac{1}{T}$

$T_1$=27${}^{\circ }$C=300 K

$d_1=d$ and $d_2=0.75d$

Now, $d_1{T}_1=d_2{T}_2$

$⟹d\times 300K=0.75d\times T_2⟹T_2=400K$

At 400 K or $127℃$ its density is 0.75d.