Question

An aqueous solution of perchloric acid is standardized by titration with a 0.191 M solution of barium hydroxide. If 13.8 mL of base are required to neutralize 17.0 mL of the acid, what is the molarity of the perchloric acid solution?

Answer 1

Answer:

Molarity of $HClO_{4}$ solution is 0.311 M

Explanation:

Neutralization reaction: $2HClO_{4}+Ba(OH)_{2}\rightarrow Ba(ClO_{4})_{2}+2H_{2}O$

According to balanced reaction, 1 mol of $Ba(OH)_{2}$ neutralizes 2 moles of $HClO_{4}$

Number of moles of $Ba(OH)_{2}$ in 13.8 mL of 0.191 M $Ba(OH)_{2}$ solution = $\frac{0.191}{1000}\times 13.8moles$ = $0.00264moles$

Let's assume molarity of $HClO_{4}$ solution is C (M) then-

Number of moles of $HClO_{4}$ in 17.0 mL of C (M) $HClO_{4}$ solution = $\frac{C}{1000}\times 17.0moles$ = $0.017Cmoles$

Hence, $0.017C=(2\times 0.00264)$

         or, $C=0.311$

So, molarity of $HClO_{4}$ solution is 0.311 M