acid-base titration

Question

Determine the number of moles of the listed first substance that would be the chemically equivalent amount of the second substance for each of these acid-base titration combinations:

Carbonous acid with 0.08 mol gallium hydroxide.

Strontium hydroxide with 8.4 x 10^-5 mol hydroiodic acid.

Phosphoric acid with 0.007 mol calcium hydroxide.

Answer 1

Ga(OH)3 = gallium hydroxide

HCO2H = carbonous acid

Ga(OH)3 + 3HCO2H -> 3H2O + Ga(CO2H)3

.08 mol Ga(OH)3 x 3 mol HCO2H / mole Ga(OH)3 = 0.24 mols HCO2H

Sr(OH)2 = strontium hydroxide

HI = hydroiodic acid

Sr(OH)2 + 2HI -> 2H2O + SrI2

8.4x10^-5 mol HI x 1 mol Sr(OH)2 / 2 mol HI = 4.2x10^-5 mol Sr(OH)2

Ca(OH)2 = calcium hydroxide

H3PO4 = phosphoric acid

3Ca(OH)2 + 2H3PO4 -> 6H2O + Ca3(PO4)2

0.007 mol Ca(OH)2 x 2 mol H3PO4 / 3 mol Ca(OH) = 0.0047 mols H3PO4

note: answers have not been corrected for sig. figs.