How can we determine the order of basicity?. ........................

We can count the no. of hydroxyl groups present for determining basicityfor example in case of phosphoric acid there are three hydroxyl group present so the order of basicity is three .Basicity tells about the acidic character of acid and is used for measurement of acidity of oxo acids

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Basisity depends on availability of line pair on donor atom. If lone pair is localised means participating in resonance it`s basisity decrease . So correct option is A) . Hope it clears. If still u have doubts then please clarify. If u like answer then please approve the answer.

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