When the temperature of a gas is raised from 27∘ C to 90∘ C, the percentage increase in the r.m.s. velocity of the molecules will be
The correct option is A. 10%.
The rms velocity of the gas molecules is given by,
vrms = √
where R = Universal gas constant
T = Temperature of the gas
M = Molar mass of the gas
Thus, for a given gas R and M are constant.
⇒ v2rmsv1rms = √ = √==1.1
% increase = (v2v1−1) ×100 = (1.1−1)×100=0.1×100= 10%.