chem
posted by rose .
if a 240mg of an acid H2A required 50.0ml of 0.10M NaOH for complete neutralization, what is yhe equivalent weight of the acid? what is its molecular weight?

0.1M NaOH = 0.1N NaOH
H2A + 2NaOH ==> Na2A + 2H2O
When the problem says "complete" neutralization, that mans BOTH H atoms have been replaced.
mL x N x m.e.w = grams.
50.00 x 0.1N x m.e.w. = 0.240g
solve for m.e.w = milliequivalent weight.
Multply by 1000 to convert to equivalent weight.
Then equivalent weight = molecular weight/replaceable Hs.
You know equivalent weight and replaceable H atoms (2), solve for molecular weight.