Chemistry. please help

A 0.12 g sample of unknown was placed in a flask and dissolved in 125 mL of deionized water. A solution of HCl (0.10 M) was used to titrate the sample, and 18 mL was required to reach the endpoint. What is the formula weight of the unknown?

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  1. The problem doesn't establish that this is a mono, di, or triprotic base but I assume one(1) OH group and we shall call it B + HCl ==> BH^+ + Cl^-
    How many moles HCl did we add to reach end point? That is M x L = ??
    moles base = same as mole HCl added.
    moles = grams/molar mass
    You know moles and grams, solve for molar mass.

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    posted by DrBob222

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