If an acid has a Ka of 1.6x10^-10 explain why it is a weak base?

Question

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Answer 1

Since K_a*K_b =1.0*10^-14, K_b = 1.0*10^-14/1.6*10^-10 =6.3*10^-5. 

K_b < 1, no complete dissociation, weak base. pK_b about 4.20

 

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