# Which of the following is the most acidic salt?

A 0.1 M solution of which salt is most acidic?

(a) Aluminum(III) nitrate $$\ce{Al(NO3)3}$$;
(b) Magnesium(II) bromide $$\ce{MgBr2}$$;
(c) Sodium bicarbonate $$\ce{NaHCO3}$$;
(d) Sodium formate $$\ce{NaHCO2}$$.

I know that it is either a or b. However, they are both product of a strong acid and a weak base reaction. How do you determine the answer?

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• sorry I made a mistake. I meant MgBr2 – Jaehyun Ahn Jan 10 at 4:02
• I've edited you question so that now it's a bit more consistent and makes a bit more sense. Feel free to verify that my edit complies with what's been written where you took the question from; also please pay more attention when asking questions: we are all people and we do make mistakes, but correctly written question is going to be answered quicker and more precisely. – andselisk Jan 10 at 5:24