Molar solubility of helium, nitrogen and oxygen are plotted against partial pressure of the gas at constant temperature.

Henry's law constant for these gases will lie in following sequences?

Which one of the following gases has the lowest value of Henry's law constant ?

Molar heat capacity of a gas at constant temperature and pressure is:

Plot density vs pressure for a fixed mass of an ideal gas at a constant temperature.

Solubility of oxygen gas in water follows Henry's law. When the solubility is plotted against partial pressure at a definite temperature we get following plot. Which of the following sequences of temperatures is correct ?