Chapter 9, Problem 116CP

The heat required to raise the temperature from $\text{300}\text{.0 K}$ to $\text{400}\text{.0 K}$ for $\text{1 mole}$ of a gas at constant volume is $\text{2079 J}$ . The internal energy required to heat the same gas at constant pressure from $\text{550}\text{.0 K}$ to $\text{600}\text{.0 K}$ is $\text{1305 J}$ . The gas does $\text{150}\text{. J}$ of work during this expansion at constant pressure. Is this gas behaving ideally? Is the gas a monatomic gas? Explain.