Question

Points I, II and III in the following plot respectively correspond to ($V_{mp} :$ most probable velocity)

• A. $V_{mp} \; of \; N_2 (300K); V_{mp} \; of \; H_2(300K); V_{mp} \; of \; O_2(400K)$
• B. $V_{mp} \; of \; H_2 (300K); V_{mp} \; of \; N_2(300K); V_{mp} \; of \; O_2(400K)$
• C. $V_{mp} \; of \; O_2 (300K); V_{mp} \; of \; N_2(300K); V_{mp} \; of \; H_2(400K)$
• D. $V _{ mp }$ of $N _{2}(300 K ) ; V _{ mp }$ of $O _{2}(400 K ) ; V _{ mp }$ of $H _{2}(300 K )$

Answer 1

Answer: (D)

$V_{mp} = \sqrt{\frac{2RT}{M} } \Rightarrow V_{mp} \propto \sqrt{\frac{T}{M}} $
For $ N_{2} , O_{2} , H_{2} $
$ \sqrt{\frac{300}{28}} < \sqrt{\frac{400}{32}} < \sqrt{\frac{300}{2}} $
$V_{mp} \; \text{of} \; N_{2} \left(300K\right) < V_{mp} \; \text{of} \; O_{2} \left(400 K\right) < V_{mp} \; \text{of} \; H_{2} \left(300 K\right) $