JEE Main 2019 — Solutions Question with Solution

Henry's law expression,

P_gas = K_H $$\times$$ x_gas

Here, P_gas = partial pressure of gas

K_H = Henry’s law constant

x_gas = mole fraction of gas

$$\because$$ x_gas = 1 - x_H2O

$$\therefore$$ P_gas = K_H $$\times$$ (1 - x_H2O)

$$\Rightarrow$$ P_gas = K_H - K_H $$\times$$x_H2O

By comparing this equation with y = mx + c,

c = K_H = Intercept

m = - K_H = slope

So in partial pressure vs mole fraction of water graph, which gas has more K_H will have more intercept. Given (K_H) are 0.5, 2, 35 and 40 kbar for w, x, y, z respectively. So intercept of z should be the most and should be the least.

As solpe is = - K_H, so slope shoul be negative for all the gases and w gas should have least negative slope and z should have highest negative slope.