The expression, Cp - R is equal to:
Correct answer: A. Cv
- A. Cv
- B. R
- C. Cp - Cv
- D. R + Cv
Explanation
The correct answer is Cv, as it represents the specific heat at constant volume. The equation Cp - R = Cv is derived from the relationship between the specific heats of gases. Specifically, for an ideal gas, the specific heat at constant pressure (Cp) is always greater than the specific heat at constant volume (Cv) by the gas constant R. Thus, when we subtract R from Cp, we arrive at Cv. The other options are incorrect because:Option B (R) is not equal to Cp - R; R is a separate constant.Option C (Cp - Cv) is not equal to Cp - R; rather, Cp - Cv equals R, which is a different relationship.Option D (R + Cv) is also incorrect; it does not derive from the relationship we are examining.Understanding these relationships is crucial in thermodynamics, particularly when dealing with ideal gases.
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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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