Chapter 18 - The Laws of Thermodynamics - Problems and Conceptual Exercises - Page 645: 29

(a) $94KJ$ into the gas (b) $92KJ$ into the gas

(a) We know that $Q=\Delta U+W$ $\implies Q=\Delta U+P\Delta V$ We plug in the known values to obtain: $Q=65+(125\times 10^3)(0.75)$ $Q=94KJ$ into the gas (b) $Q=\Delta U+W$ $\implies Q=\Delta U+P\Delta V$ We plug in the known values to obtain: $Q=-1850+(125\times 10^3)(0.75)$ $Q=92KJ$ into the gas