The Henry's law constant for the solubility of $\mathrm{N}_2$ gas in Water at 298 K is $1 \times 10^5 \mathrm{~atm}$. The mole fraction of air is 0.8 . The number of moles of $\mathrm{N}_2$ from air dissolved in 10 moles of water at 298 K and 5 atm pressure is

What is the effect of external pressure on the osmotic pressure (OP) of a solution?

Which of the following is/are "not correct" for $\mathrm{CH}_3 \mathrm{OH}+\mathrm{CH}_3 \mathrm{COOH}$ mixture solution?

1. 1. $\Delta H_{\text {mix }}<0$

2. 2. Does not obey Raoult's law.

3. 3. $\Delta H_{\text {mix }}>0$

4. 4. An example of ideal solution.

Henry's law is valid for

(A) ammonia gas dissolution in water

(B) $\mathrm{O}_2$ gas dissolution in unsaturated blood

(C) $\mathrm{O}_2$ dissolution in water

(D) $\mathrm{CO}_2$ dissolution in water