WilliamSlim
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#1
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#1
I've looked at it in the book for the past 3 hours and still don't understand it, or this question.

http://i.imgur.com/MQeTcUIh.jpg

Can someone run me through this? I looked at the mark sscheme and have no idea where the value 0.24 came from, it's supposed to be 0.64. My teacher said if you subtract 0.40 from 0.64 you get 0.24 but I have no idea why you are supoised to do that, nor do I have any idea how buffers are formed.
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Pigster
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Do you know the amounts of the acid and alkali at the start? What will happen to the amount of acid when you add the alkali to it? What will the alkali become?
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EierVonSatan
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You have an acid base reaction:

acid + base ---> salt + water

Start: 0.4 mol of base, 0.64 mol of acid, 0 mol of water, 0 mol of salt

End: 0 mol of base, 0.24 mol of acid, 0.4 mol water, 0.4 mol salt
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Pigster
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Those numbers.

The 0.4 mol of water isn't required for the calculation (but it is nice to remember that it is made - water is so often underappreciated)
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WilliamSlim
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(Original post by EierVonSatan)
You have an acid base reaction:

acid + base ---> salt + water

Start: 0.4 mol of base, 0.64 mol of acid, 0 mol of water, 0 mol of salt

End: 0 mol of base, 0.24 mol of acid, 0.4 mol water, 0.4 mol salt
How do I know when to carry out this calculation and that there is jo base?
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Borek
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When you mix acid and base you can expect neutralization reaction, that's rather normal, isn't it?
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