Water contains about 42 mg of oxygen per liter at 20 $\circ$ C and 1 atm.What is the Henry's law constant for oxygen dissolving in water?

Question

Quizplus · Accepted Answer

Henry's law can be written as: 
P = K_H * C 
where P is the partial pressure of the gas above the solution, C is the concentration of the gas in the solution, and K_H is the Henry's law constant. 
At 1 atm, the concentration of oxygen in water at 20°C is 42 mg/L, which is equal to 0.042 g/L or 0.00262 mol/L. 
Therefore, using the given values, we can calculate the Henry's law constant as:

K_H = P/C = 1 atm / 0.00262 mol/L = 3.82 x 10^2 mol/L*atm

This value is closest to option B, 1.3 x 10^4 mol/L*atm (after correcting the typo in the units given in the option).

Water Contains About 42 Mg of Oxygen Per Liter at 20