If for a gas (R/Cv)=0.67 this gas is made up of molecules which are:
Correct answer: C. Monoatomic
- A. Diatomic
- B. Mixture of diatomic and polyatomic
- C. Monoatomic
- D. Polyatomic
Explanation
Ratio R/Cv is related to degrees of freedom (f) by Cv = (f/2)R, so R/Cv = 2/f. Given R/Cv ≈ 0.67 (or 2/3), we can solve for f: 2/f = 2/3, which gives f=3. A gas with 3 degrees of freedom (for translational motion only) is monoatomic gas.
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About Molar Specific Heat of a Gas
Molar specific heat is the heat required to raise the temperature of one mole of a gas by one kelvin, expressed through Q = nCΔT. Questions compare the constant volume value Cv with the constant pressure value Cp, apply the ideal gas relation Cp − Cv = R, and identify how the thermodynamic process affects heat capacity.
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