Maleic acid is a carbon-hydrogen-oxygen compound used in dyeing and finishing fabrics and as a preservative of oils and fats.

* In a combustion analysis, a 1.054-\rm g sample of maleic acid yields 1.599 \rm g of \rm CO_2 and 0.327 \rm g of \rm H_2O.
* When 0.609 \rm g of maleic acid is dissolved in 25.00 \rm g of glacial acetic acid, the freezing point drops by 0.82 ^\circ \rm C. Maleic acid does not ionize in glacial acetic acid, which has a freezing-point depression constant of K_{\rm f}=3.90~^\circ {\rm C}/m.
* In a titration experiment, a 0.4250-\rm g sample of maleic acid is dissolved in water and requires 34.03 \rm mL of 0.2152 M \rm KOH for its complete neutralization.
* The \rm pH of 0.215 \rm g of maleic acid in 50.00 \rm mL of aqueous solution is found to be 1.80.
Part A
Determine the empirical formula for maleic acid. Enter the atoms in order of \rm C, \rm H, and \rm O.
Part B
Determine the molecular formula for maleic acid. Enter the atoms in order of \rm C, \rm H, and \rm O.
Express your answer as a chemical formula.
Part C
Based on the titration data, how many ionizable \rm H atoms are in each molecule of maleic acid, \rm C_4H_4O_4?
Express your answer as an integer.
I GOT THE PART A and B which is CHO and C_4H_4O_4 respectively, can anyone help me for part C?

4 answers

part c.
mols C4H4O6 = grams/molar mass = 0.4250/116.07 = 0.00366

mols KOH added = L x M = 0.03403 x 0.2152 = 0.00732. Therefore, the KOH must have titrated 2 H ions (from 0.007323/0.0036615) = 1.99995 = 2.0

Thank you very much.

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