CH3COOH/CH3COONA BUFFER

CH3COOH is a weak acid and doesnt fully dissociate in water. Whereas CH3COONa is a salt which will fully dissolve in water into Na+ & CH3COO-


And additionally that CH3COO- from the salt pushing the acid's own dissociation balance backwards.

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the Ka of CH3COOH is very small so the equillibrium is lớn the left (reactants) an this reaction produces little products (here CH3COO-). NaCH3COO is good solluble so every mole of NaCH3COO produce a mole of CH3COO-. The amount CH3COO- produced by CH3COOH is neglectIble in relation khổng lồ CH3COO- produced by NaCH3COO.


This. It's just a trick to simplify the calculation since otherwise you have to divide by from acetate + from acetic acid. Where from acid will equal .

Having calculated the answer you can try to include the addition and you'll see its the same answer to lớn within significant figures.

You can use this approximation since the Ka of weak acids are so low.

I.E the equation should be: Ka = * ( + ) /

Where x = = from the acetic acid.

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I'll also địa chỉ we can assume sodium acetate is 100% dissociated since sodium is part of a strong base (NaOH). Therefore it too must completely dissociate.


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level 1
· 6 mo. Ago

Just adding lớn what others have said, the general equation is Ka = /

You make assumptions for simplicity that in the buffer = undissociated acid concentration & = salt conc.

Ka = /


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level 1
· 6 mo. Ago

Bro I miss highschool chemistry :(. My grade 12 chem class was definitely the most fun và interesting science class I’ve taken lớn date. Might decide khổng lồ take it next semester lớn fulfil one of my science credit requirements.


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level 1
· 6 mo. Ago

CH3COOH is a weak acid, thus it won’t ionize completely. Meaning, =/= and that we have khổng lồ solve for the concentration of the Acetate ion.

However, CH3COONa is a salt. Therefore, will completely (100%) ionize into acetate và sodium ions. I.e., = upon dissociation.


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level 1
· 6 mo. Ago
level 2
· 6 mo. Ago
Inorganic

It's spelled "We're", & no you're not lol.


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level 1
· 6 mo. Ago

R u from India.. Và in class 11th? .. Cause my teacher is also teaching me the equilibrium chapter.. XD... + Sodium acetate is completely ionised that's why its not taken from there


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