The solubility of NH3 in H2O is 518 g/L at a partial pressure of 760.0 torr.

a. Calculate the value of the Henry's Law constant for NH3

b. Calculate the solubility of NH3 in H2O at a partial pressure of 225.0 torr.

2 answers

Henry's Law constant is quote numerous ways. I will use the equation of Pgas = k*c so k = P/c = value in units of atm*L/moles.
Convert 518 g/L to moles NH3 and substitute into Henry's Law equation I show above along with P of 1 atm and evaluate k. Then redo the equation using 225 torr (convert to atm first) and solve for molar concn NH3 at that reduced pressure.
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