Acetic acid is a weak acid .Why?

Acetic acid, CH3COOH , is a weak acid, because it is present in solution primarily as whole CH3COOH molecules, and very little as H+ and CH3COO− ions. Which furthermore indicates that acetic acid is weak, because strong ions ionize almost completely.

weak acid

Explanation:

because it is present in solution primarily as whole CH3COOH molecules

the answer is:  

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