[kdbmvp]

Hello,

How much N₂ can be solved in 1L of water at 20 celsius, 1 atm total pressure, if the partial pressure of the N₂ gas is 0.78atm? From a table I found that the solubility of N₂ in water at 20 celsius is 0.0190 g/L, at a total pressure of 1 atm. The solution manual calculates it this way:
0.78atm*0.0190 g/L = 0.01482 g/L. But is this correct? From how I understand the task the answer should just be 0.0190 g/L

[Enthalpy]

What does this "total pressure" mean? If it's 1atm of air, then 0.78atm of N₂ is reasonable. If it's 1atm of N₂, you need to scale down to 0.78atm.

[kdbmvp]

Total pressure was probably the wrong word. It just says: how much N₂ can be solved in 1L of water at 20 celsius and 1 atm pressure. Not sure if I entirely understood your answer?

[Borek]

Total pressure was probably the wrong word. It just says: how much N₂ can be solved in 1L of water at 20 celsius and 1 atm pressure. Not sure if I entirely understood your answer?

Amount of nitrogen dissolved will depend on the partial pressure of nitrogen, other gases don't matter (or rather: effect of their presence ins negligible). What is the partial pressure of nitrogen?

[kdbmvp]

The partial pressure of N₂ is 0.78 atm

[Borek]

As Enthalpy wrote: assuming the data given was solubility for 1 atm of nitrogen, you should scale the solubility to 0.78 atm (remembering what Henry's law says).