October 15, 2021, 03:32:20 PM
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Topic: Solving for pH using ideal gas law  (Read 1311 times)

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Offline Dedora

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Solving for pH using ideal gas law
« on: August 13, 2021, 06:39:16 PM »
I had this question on my chemistry assignment:

A 250 mL sample of gaseous hydrogen bromide, measured at 23.7°C and .945 atm, was dissolved in sufficient pure water to form 250 mL of solution. What was the pH of the solution?

So I used PV=nRT to solve for n
(.945*.25)/(.0821*296.85)
n=.00969

This is where I'm unsure:
.00969/.250=.03877
-log[.03877]= 1.411

Should n be divided by 250 mL or is it a different number?

Offline Borek

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Re: Solving for pH using ideal gas law
« Reply #1 on: August 14, 2021, 03:03:48 AM »
Looks OK.

Yes, you are told "to form 250 mL of solution", so that's the volume that should be used for concentration calculation.
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