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

Assertion: $A$ mixture of $He$ and $O_2$ is used for respiration for deep sea divers.
Reason: $He$ is soluble in blood.

Calculate the pressure of the gas if the solubility of the gas in water at $25^{\circ} C$ is $6.85 \times 10^{-4} \ mol \ dm^{-3}$. (Henry's law constant $K_H$ is $6.85 \times 10^{-4} \ mol \ dm^{-3} \ bar^{-1}$) (in $bar$)

State Henry's law and mention some important applications.

$CO_2$ gas is bubbled through water during a soft drink manufacturing process at $298 \ K$. If $CO_2$ exerts a partial pressure of $0.835 \ bar$,then $x \ mmol$ of $CO_2$ would dissolve in $0.9 \ L$ of water. The value of $x$ is $.....$ (Nearest integer).
(Henry's law constant for $CO_2$ at $298 \ K$ is $1.67 \times 10^3 \ bar$)

$A$ company dissolves '$X$' amount of $CO_{2}$ at $298 \ K$ in $1 \ L$ of water to prepare soda water. $X = ........ \ \times 10^{-3} \ g$ (nearest integer).
(Given: partial pressure of $CO_{2}$ at $298 \ K = 0.835 \ bar$.
Henry's law constant for $CO_{2}$ at $298 \ K = 1.67 \ kbar$.
Atomic mass of $H$,$C$ and $O$ is $1$,$12$ and $16 \ g \ mol^{-1}$,respectively.)