Question

43.0 mL of 1.49 M perchloric acid is added to 14.0 mL of calcium hydroxide, and the resulting solution is found to be acidic.

29.1 mL of 0.498 M barium hydroxide is required to reach neutrality.

What is the molarity of the original calcium hydroxide solution?

Answer 1

2.29 M

Step-by-step explanation:

Equation of the reaction;

Ca(OH)2(aq) + 2HClO4(aq) → 2H2O(l) + Ca(ClO4)2(aq)

Concentration of acid CA = 1.49 M

Concentration of base CB= ????

Volume of acid VA= 43.0 ml

Volume of base VB= 14.0 ml

Number of moles of acid NA = 2 moles

Number of moles of base NB = 1 mole

CAVA/CBVB = NA/NB

CAVANB =CBVBNA

CB= CAVANB/VBNA

CB= 1.49 × 43.0 × 1/14.0 × 2

CB= 2.29 M