Consider a mixture of n moles of helium gas and 2n moles of oxygen gas (molecules taken to be rigid) as an ideal gas. Its CP/CV value will be :
Solution
$${{{C_P}} \over {{C_V}}} = {{{n_1}{C_{{P_1}}} + {n_2}{C_{{P_2}}}} \over {{n_1}{C_{{V_1}}} + {n_2}{C_{{V_2}}}}}$$
<br><br>= $${{n \times {{5R} \over 2} + 2n \times {{7R} \over 2}} \over {n \times {{3R} \over 2} + 2n \times {{5R} \over 2}}}$$
<br><br>= ${{5 + 14} \over {3 + 10}}$
<br><br>= ${{19} \over {13}}$
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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