Question

The density of a gas An is three times that of a gas B. if the molecular mass of A is M, the molecular mass of B is

• A. 3 M
• B. $\sqrt { 3 }$M
• C. $M / 3$
• D. $M / \sqrt { 3 }$

Answer 1

Answer: (C)

$M / 3$

Answer 2

$d \propto M$ ⇒ $\frac { d _ { 1 } } { d _ { 2 } } = \frac { M _ { 1 } } { M _ { 2 } }$ ; $\frac { 3 d } { d } = \frac { M } { M _ { 2 } }$ ; $M _ { 2 } = \frac { M } { 3 }$ .