O₂ is bubbled through water at 293K, assuming that O₂ exerts a partial pressure of 0.98 bar, the solubility of O₂ in gm.L–1 is (Henry's law constant = 34 k bar)
 

O₂ is bubbled through water at 293 K, and the partial pressure of O₂ is 0.98 bar. The Henry's law constant is 34 k bar. Calculate the solubility of O₂ in water.

1. Henry's Law

Henry's law relates the solubility of a gas in a liquid to the partial pressure of the gas. The equation is:

p_O2 = K_H * χ_O2

• p_O2 = Partial pressure of O₂ (in bars)
• K_H = Henry's law constant (in k bar)
• χ_O2 = Mole fraction of O₂ in water

2. Calculating Mole Fraction of O₂

Rearranging the formula for mole fraction, we get:

χ_O2 = p_O2 / K_H

Substitute the given values:

χ_O2 = 0.98 / (34.84 * 10³) = 2.81 * 10^-5

3. Moles of O₂

The mole fraction is related to the moles of O₂ and the moles of water (H₂O) by:

χ_O2 = n_O2 / (n_O2 + n_H2O)

For 1 L of water, the number of moles of water is approximately 55.55. We can now calculate the number of moles of O₂:

χ_O2 ≈ n_O2 / 55.55

n_O2 = 2.81 * 10^-5 * 55.55 = 1.56 * 10^-3 mol

4. Solubility in Grams per Liter

The solubility of O₂ in water is calculated by multiplying the number of moles of O₂ by its molar mass (32 g/mol for O₂).

Solubility of O₂ = 1.56 * 10^-3 * 32 = 0.05 g/L

Conclusion:

The solubility of O₂ in water at 293 K is 0.05 g/L.