# A 15.0-mL solution of 12 M HCl is diluted with 200 mL of water. What is the new concentration of...

## Question:

A 15.0-mL solution of 12 M HCl is diluted with 200 mL of water. What is the new concentration of the acid solution?

## Dilution:

Commercially available hydrochloric acid solution is sold at a higher concentration of hydrochloric acid. Solutions of lower concentration of hydrochloric acid can be prepared by dilution.

## Answer and Explanation: 1

Use the dilution equation;

{eq}\rm \\ C_1V_1 = C_2V_2 \\ Where; \\ C_1 = Initial \ concentration = 12 \ M \\ V_1 = Initial \ volume = 15.0 \ mL \\ C_2 = Final \ concentration = \ ? \\ V_2 = Final \ volume = 15.0 \ mL + 200 \ mL = 215 \ mL \ (assuming \ volume \ is \ additive) {/eq}

Rearrange the equation to solve for final concentration {eq}\rm (C_2) {/eq}

{eq}\rm C_2 = \dfrac{C_1V_1}{V_2} {/eq}

Plug in the values and solve for final concentration {eq}\rm (C_2) {/eq}

{eq}\rm C_2 = \dfrac{12 \ M \times 15.0 \ mL}{215 \ mL} = \textbf{0.84 M} {/eq}