Q: The value of C_{P} – C_{V} = 1.00 R for a gas in state A and C_{P} – C_{V} = 1.06R in another state. If P_{A} and P_{B} denote the pressure and T_{A} and T_{B} denote the temperatures in the two states, then

(a) P_{A} = P_{B}, T_{A} > T_{B}

(b) P_{A} > P_{B}, T_{A} = T_{B}

(c) P_{A} < P_{B}, T_{A} > T_{B}

(d) P_{A} = P_{B}, T_{A} < T_{B}

Ans: (c)

Sol: For Ideal gas

C_{P} – C_{V} = R (for State A)

But for state B ,

C_{P} – C_{V} = 1.06R

Hence it does not behave like an ideal gas .

As we know that for ideal gas pressure should be low & temperature should be high .

P_{A} < P_{B} & T_{A} > T_{B}