Question 33: Thermodynamics & KTG

Question

When 2 moles of a monoatomic gas are mixed with 3 moles of a diatomic gas, the value of adiabatic exponent for the mixture is

Accepted Answer

Let, $$\gamma$$ be the adiabatic exponent for the mixture.
For monoatomic gas,
n
1
= 2 and $$\gamma$$
1
= $${{5} \over {3}}$$
For diatomic gas,
n
2
= 3 and $$\gamma$$
2
= $${{7} \over {5}}$$
For the mixture,
$${{{n_1} + {n_2}} \over {\gamma  - 1}} = {{{n_1}} \over {{\gamma _1} - 1}} + {{{n_2}} \over {{\gamma _2} - 1}}$$
Substituting all the given values in above equation, we get
$${{2 + 3} \over {\gamma  - 1}} = {2 \over {{5 \over 3} - 1}} + {3 \over {{7 \over 5} - 1}}$$
$$ \Rightarrow {5 \over {\gamma  - 1}} = {{21} \over 2} \Rightarrow \gamma  = {{31} \over {21}}$$

Answer

$${{15} \over {16}}$$

Answer

$${{7} \over {5}}$$

Answer

$${{31} \over {21}}$$

Answer

$${{38} \over {59}}$$

Thermodynamics & KTG

When 2 moles of a monoatomic gas are mixed with 3 moles of a diatomic gas, the value of adiabatic exponent for the mixture is

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