Yazomi
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For questions like this, is this theory right?

So if you add salt to an acid, you’ll just sub the concentration into the equation to find out the concentration of H^+ ions

If it’s acid add base (NaOH) - mole of acid take away mole of base before subbing calculated concentration into the equation



If it’s acid, base and salt mixed together- let’s say base =5moles
Mole of acid -5
Calculate conc and sub into equation

Mole of salt +5
Calc concentration and sub into the equation ?
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CJField
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(Original post by Yazomi)
Name:  97AD7B66-1B04-4759-A31C-19448F481D93.jpg.jpeg
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For questions like this, is this theory right?

So if you add salt to an acid, you’ll just sub the concentration into the equation to find out the concentration of H^+ ions

If it’s acid add base (NaOH) - mole of acid take away mole of base before subbing calculated concentration into the equation



If it’s acid, base and salt mixed together- let’s say base =5moles
Mole of acid -5
Calculate conc and sub into equation

Mole of salt +5
Calc concentration and sub into the equation ?
not sure what you mean but to calculate pH of a buffer, you will need to use the Ka equation to find out [H+]. This involves finding the conc of the acid, the conc of the salt added, rearranged to solve for [H+], and subbing it into pH equation.
Last edited by CJField; 2 months ago
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pipthesqueak
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you will need to use the Ka formula for dissociation of methanoic acid which is:
Ka = [HCOO-][H+] / [HCOOH]
sodium methanoate dissociates into Na+ and HCOO- so the [HCOO-] is equal to the conc of sodium methanoate
use the Ka value given, the conc of sodium methanoate and methanoic acid to sub back into the Ka equation to work out [H+], which you can then use to work out pH
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