Question

The titration of a 25.00 mL sample of NaOH required 28.25 mL of a 0.200 M HCl solution to reach the end point. What was the molar concentration of the sodium hydroxide solution?

Answer 1

Answer:

Mb = 0.226 M

Explanation:

This is a acid base titration between a strong acid and a strong base, therefore, this reactions is completely done, and the reaction is the following:

NaOH + HCl -------> NaCl + H2O

We have here a 1:1 mole ratio, this means that:

1 mole NaOH = 1 mole HCl

Expressing in concentration and volume:

Mb * Vb = Ma * Va

We have concentration and volume of the acid, and the volume of the base, so we can solve for the concentration:

Mb = Ma * Va / Vb

Mb = 28.25 * 0.2 / 25

Mb = 0.226 M

This is the concentration of the NaOH solution