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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: AE35 on December 05, 2010, 12:07:32 PM

Title: Calculating pH from mass in grams and volume?
Post by: AE35 on December 05, 2010, 12:07:32 PM

Hey all!

This is my first post here! :)

I'm trying to lean back into chemistry, but I need some help and explanation that
I hope you can help me with.

I'm to calculate pH in wine that contains 1.72 g monosodium tartrat(E335) per liter.
(pH is only calculated from that salt in the solution)

The molar mass of monosodium tartrat is 172,07 g/mol

I would be very happy if someone could tell me hwo to approach and solve this
problem.

Thanks,

Nicholas

Title: Re: Calculating pH from mass in grams and volume?
Post by: Borek on December 05, 2010, 01:47:55 PM

First step - mass and volume to molarity.

Title: Re: Calculating pH from mass in grams and volume?
Post by: AE35 on December 05, 2010, 02:48:31 PM

Well, should I take the 1.72 g and divide by the molar mass:

1.72 g / (172.07 g/mol)  =  0.009996 mol ?

...And then divide the moles with the volume(1 L)? This will give M = 0.009996

Thanks! Standing by for advice:)

Title: Re: Calculating pH from mass in grams and volume?
Post by: Borek on December 05, 2010, 03:33:15 PM

Instead of standing by you should be working on calculation pH of the tartrate. Have you checked what it is? Ka values? We can help, but don't expect spoon feeding.

Title: Re: Calculating pH from mass in grams and volume?
Post by: AE35 on December 05, 2010, 03:52:06 PM

Do you think you might put a little too much into the 'standing-by' statement?

You really think that I gave the impression that I wanted to be spoon fed? After two
whole posts?

Bye