Question

A 14.0 mL sample of acetic acid requires 28.23 mL of a 0.521 M solution of NaOH for titration to the equivalence point. What is the concentration of the acetic acid?

Answer 1

Answer:

Concentration of the acid = 1.05M

Explanation:

Given parameters:

Volume of acid = 14.0mL = 0.014L

Volume of base = 28.23mL = 0.02823L

Concentration of the base = 0.521M

Unkown:

Concentration of acid = ?

The reaction equation is given below:

          CH₃COOH + NaOH → CH₃COONa + H₂O

To obtain the unknown concentration of the acid used in the reaction, we simply work from the known parameters of the given base.

Procedure:

• Find the number of moles of the base used in the reaction using the equation below:

       Number of moles of base = concentration of base x volume

      Number of moles of base = 0.521 x 0.02823 = 0.0147mol

• From the balanced reaction equation, we know that:

      1mole of the base neutralize on mole of acid,

    Therefore, 0.0147mol of the acid would be neutralized by the base.

To find the concentration of the acetic acid,

Concentration of acid = $\frac{Number of moles of acid}{Volume of acid}$

Concentration of acid = $\frac{0.0147}{0.014}$

Concentration of the acid = 1.05M