Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: If the average kinetic energy of ${\mathrm{H}}_{2}$ and ${\mathrm{O}}_{2}$ molecules, kept in two different sized containers are same, then their temperatures will be same.
Reason R: The r.m.s. speed of ${\mathrm{H}}_{2}$ and ${\mathrm{O}}_{2}$ molecules are same at same temperature.
Choose the correct answer from the options given below.

[04 April, 2026 (Shift-II)]

Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: If the average kinetic energy of ${\mathrm{H}}_{2}$ and ${\mathrm{O}}_{2}$ molecules, kept in two different sized containers are same, then their temperatures will be same.
Reason R: The r.m.s. speed of ${\mathrm{H}}_{2}$ and ${\mathrm{O}}_{2}$ molecules are same at same temperature.
Choose the correct answer from the options given below.

[04 April, 2026 (Shift-II)]

YESPYQ · Accepted Answer

Correct answer: c) A is true but R is false. Assertion A: Average $\mathrm{KE}=\frac{3}{2}kT$, which depends only on temperature, not on the type of gas or container size. So if KE is same → Temperature is same. (A is TRUE) Reason R: RMS speed $-\sqrt{\frac{3RT}{M}}$, which depends on molar mass. Since ${M}_{{H}_{2}}\neq {M}_{{O}_{2}}$, their rms speeds differ at same temperature. ( R is FALSE)

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: If th…

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