The specific heat at constant pressure (C_P) | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) By definition,specific heat at constant volume $(C_V)$ is the heat required to raise the temperature of $1 	ext{ mole}$ of a gas by $1 	ext{ K}$

Vedclass · Accepted Answer

At constant pressure,work is done in expanding the gas.

Vedclass · Answer

(A) By definition,specific heat at constant volume $(C_V)$ is the heat required to raise the temperature of $1 	ext{ mole}$ of a gas by $1 	ext{ K}$ while keeping the volume constant. In this case,no external work is done $(W = 0)$,so all the heat supplied is used to increase the internal energy of the gas.However,at constant pressure $(C_P)$,when heat is supplied to the gas,it not only increases the internal energy but also performs external work $(W = P \Delta V)$ to expand the gas against the constant external pressure.According to the first law of thermodynamics,$\Delta Q = \Delta U + W$. Since $C_P$ requires additional energy to perform this expansion work,more heat must be supplied to achieve the same temperature rise compared to the constant volume process. Therefore,$C_P > C_V$.

Column-$I$	Column-$II$
$(a)$ Monoatomic gas	$(i)$ ${C_P} = \frac{3}{2}R$
$(b)$ Diatomic gas with vibration	$(ii)$ ${C_P} = \frac{5}{2}R$
	$(iii)$ ${C_P} = \frac{7}{2}R$
	$(iv)$ ${C_P} = \frac{9}{2}R$

The specific heat at constant pressure $(C_P)$ is greater than the specific heat at constant volume $(C_V)$ for the same gas because:

Similar Questions

If $\frac{R}{C_v} = 0.67$,identify the gas.

If a gas has $n$ degrees of freedom,the ratio of specific heats of the gas is:

Select the incorrect relation. (Where symbols have their usual meanings)

Write the value of $\gamma$ for a polyatomic gas.

Vedclass Test Series

Exam Paper Generator

Online Exam Module