SATHEE: States of Matter - Result Question 27

States of Matter - Result Question 27

####27. The root mean square speeds at STP for the gases $H_{2}, N_{2}, O_{2}$ and $H B r$ are in the order: [1991]

(a) $H_{2} < N_{2} < O_{2} < H B r$

(b) $H B r < O_{2} < N_{2} < H_{2}$

(d) $H B r < O_{2} < H_{2} < N_{2}$ .

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Solution:

(b) $P V = \frac{1}{3} m N u^{2} = \frac{1}{3} M u^{2}$

or $u = \sqrt{3 P V / M}$ .

At STP, $u \propto \sqrt{\frac{1}{M}}$

i.e. higher will be the molar mass, lower will be the value of $u_{r m s}$ .

Molecular masses of $H_{2}, N_{2}, O_{2}$ and $H B r$ are 2, 28, 32 and 81. Hence the correct order of $u_{r m s}$ will be $H B r < O_{2} < N_{2} < H_{2}$

States of Matter - Result Question 27

Solution:

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States of Matter - Result Question 27

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

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