Calculate the solubility of gas in water at $1.2 \text{ atm}$ and $25^{\circ} C$ if Henry's law constant is $0.45 \text{ mol dm}^{-3} \text{ atm}^{-1}$ at $25^{\circ} C$.

Assertion : The molecules of the dissolved gas present in a liquid gain kinetic energy as temperature is raised.
Reason : Gases tend to be more soluble in liquids as the temperature is raised.

Observe the following data given in the table $(K_H = \text{Henry's law constant})$. The correct order of solubility of these gases is:

Gas	$K_H$ (kbar at $298 \ K$)
$CO_2$	$1.67$
$Ar$	$40.3$
$HCHO$	$1.83 \times 10^{-5}$
$CH_4$	$0.413$

Which one of the following statements regarding Henry's law is not correct?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: Helium is used to dilute oxygen in diving apparatus.
Reason $R$: Helium has high solubility in $O_2$.
In the light of the above statements,choose the correct answer from the options given below:

Henry's law constant for the solubility of $N_2$ gas in water at $298\, K$ is $1.0 \times 10^5\, atm$. The mole fraction of $N_2$ in air is $0.6$. The moles of $N_2$ from air dissolved in $10$ moles of water at $298\, K$ and $5\, atm$ pressure is