Question

At 0°C the density of a fixed mass of a gas divided by pressure is x. At 100°C, the ratio will be

• A. x
• B. $\frac{273}{373}x$
• C. $\frac{373}{273}x$
• D. $\frac{100}{273}x$

Answer 1

Answer: (B)

$\frac{273}{373}x$

Answer 2

$PV = \mu RT = \frac{m}{M}RT$Ž $\frac{m}{VP}$Ž$\frac{\text{density}}{P} = \frac{M}{RT}$

$\left( \frac{\text{density}}{P} \right)_{At\mspace{6mu} 0{^\circ}C} = \frac{M}{R(273)} = x$ …...(i)

$\left( \frac{\text{density}}{P} \right)_{At\mspace{6mu} 100{^\circ}C} = \frac{M}{R(373)}$ …..(ii)

Ž $\left( \frac{\text{density}}{P} \right)_{At\mspace{6mu} 100{^\circ}C} = \frac{273x}{373}$