Consider a mixture of gas molecule of types A, B and C having masses mA < mB < mC. The ratio of their root mean square speeds at normal temperature and pressure is :
Solution
rms velocity of gas molecules is given as<br/><br/>${v_{rms}} = \sqrt {{{3RT} \over m}}$ ..... (i)<br/><br/>where, m = molar mass of the gas in kilograms per mole,<br/><br/>R = molar gas constant,<br/><br/>and T = temperature in kelvin.<br/><br/>According to question,<br/><br/>m<sub>A</sub> < m<sub>B</sub> < m<sub>C</sub><br/><br/>From Eq. (i),<br/><br/>${v_{rms}} \propto {1 \over {\sqrt m }}$<br/><br/>$\therefore$ We can write,<br/><br/>v<sub>A</sub> > v<sub>B</sub> > v<sub>C</sub> or ${1 \over {{v_A}}} < {1 \over {{v_B}}} < {1 \over {{v_C}}}$
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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