Question

You are performing a titration with 0.80 M sodium hydroxide as a standard. Estimate how much would be needed to change 125 mL of a 2.0 M solution of nitric acid to a faint pink endpoint.

Answer 1

312.5 mL

Step-by-step explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

HNO₃ + NaOH —> NaNO₃ + H₂O

From the balanced equation above,

The mole ratio of acid, HNO₃ (nₐ) = 1

The mole ratio of base, NaOH (n₆) = 1

Finally, we shall determine the volume of the base, NaOH needed for the reaction. This can be obtained as follow:

Molarity of base, NaOH (M₆) = 0.08 M

Volume of acid, HNO₃ (Vₐ) = 125 mL

Molarity of acid, HNO₃ (Mₐ) = 2 M

Volume of base, NaOH (V₆) =?

MₐVₐ / M₆V₆ = nₐ/n₆

2 × 125 / 0.80 × V₆ = 1/1

250 / 0.80 × V₆ = 1

Cross multiply

0.80 × V₆ = 250

Divide both side by 0.8

V₆ = 250 / 0.8

V₆ = 312.5 mL

Thus, the volume of the base, NaOH needed for the reaction is 312.5 mL