### Topic: Calculate solubility of gases  (Read 679 times)

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#### kdbmvp

• Regular Member
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• Mole Snacks: +0/-0 ##### Calculate solubility of gases
« on: February 21, 2019, 05:25:48 AM »
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 ##### Re: Calculate solubility of gases
« Reply #1 on: February 21, 2019, 06:10:37 AM »
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

• Regular Member
•   • Posts: 19
• Mole Snacks: +0/-0 ##### Re: Calculate solubility of gases
« Reply #2 on: February 21, 2019, 07:09:27 AM »
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 ##### Re: Calculate solubility of gases
« Reply #3 on: February 21, 2019, 09:30:27 AM »
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?
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#### kdbmvp

• Regular Member
•   • Posts: 19
• Mole Snacks: +0/-0 ##### Re: Calculate solubility of gases
« Reply #4 on: February 22, 2019, 06:53:23 AM »
The partial pressure of N2 is 0.78 atm

#### Borek ##### Re: Calculate solubility of gases
« Reply #5 on: February 22, 2019, 02:46:14 PM »
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).
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info, pH-meter.info, PZWT_s1