Propanoic acid, CH3CH2COOH, is a weak acid used as a food preservative. In water it sets up the equilibrium below.
CH3CH2COOH(aq) ⇌ CH3CH2COO−(aq) + H+(aq)
State what is meant by the term weak when applied to propanoic acid.
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Write an expression for the acid dissociation constant, Ka, for propanoic acid.
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The expression [H+]2 ÷ [CH3CH2COOH] is sometimes used in calculations. Explain why this is not the general definition of Ka.
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