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Topic: calculating Kb  (Read 2220 times)

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Offline mbas

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calculating Kb
« on: September 27, 2014, 08:13:38 AM »
Hi,

I have a problem with one off my school assignments.
I need to calculate the kB from Ethylamine with only 0,1 M  Hydrochloric acid  and a pH Measuring instrument. I have no idea where to start  :'(
It would be lovely if someone could help me, it would mean a lot to me.
(sorry for the bad english, I'm dutch)

x

Offline Borek

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Re: calculating Kb
« Reply #1 on: September 27, 2014, 10:47:26 AM »
You need to record the titration curve - Kb (and Ka) can be read from that.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline mbas

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Re: calculating Kb
« Reply #2 on: September 27, 2014, 11:04:59 AM »
You need to record the titration curve - Kb (and Ka) can be read from that.

Yeah but the thing is we have to calculate it. I need to use the acid and the pH measuring instrument to do that.

Offline Borek

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Re: calculating Kb
« Reply #3 on: September 27, 2014, 12:33:20 PM »
You will need some calculations, but there is no other way.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Arkcon

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Re: calculating Kb
« Reply #4 on: September 27, 2014, 10:36:36 PM »
And like you say, mbas:, you also need to use the equipment and reagents to generate data for your curve.  See if your textbook or class notes gives you the basic idea of what titration is, and let us know if you're still stuck with something minor.  You can probably begin to know "where to start" -- at least tell us you know which part goes where.
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

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