🧪 Chemistry · States of Matter · NEET & JEE

Which of the following correctly compares the most probable (u_mp), average (u_av) and root-mean-square (u_rms) speeds of gas molecules?

Answer: u_rms is largest, u_mp is smallest.

A u_rms is largest, u_mp is smallest
B u_mp is largest, u_rms is smallest
C all three speeds are exactly equal
D u_av is the largest of the three

Correct answer: A. u_rms is largest, u_mp is smallest

Explanation: For a gas the speeds rank as u_mp : u_av : u_rms = 1 : 1.128 : 1.224, so u_rms is the greatest and u_mp the least.

Graph of pressure versus volume for a fixed amount of gas at constant temperature: the curve falls steeply then flattens, a hyperbola showing pressure inversely proportional to volume.

Boyle's law: at constant temperature the pressure of a fixed mass of gas is inversely proportional to its volume (P ∝ 1/V), so the P–V plot is a hyperbola — halving the volume doubles the pressure. Image: Reginaprice2013, CC BY-SA 3.0, via Wikimedia Commons.

Concept context

Discover why gases expand to fill any container while liquids flow and solids hold their shape. Master the gas laws, the ideal gas equation, and the reasons real gases deviate from ideal behavior.

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Which of the following correctly compares the most probable (ump), average (uav) and root-mean-square (urms) speeds of gas molecules?

Concept context

More States of Matter questions

Which of the following correctly compares the most probable (u_mp), average (u_av) and root-mean-square (u_rms) speeds of gas molecules?