Question

If 15.8 mL of 7.5 M HCI is used to make a 743.9 mL aqueous solution, what is the molarity of the dilute solution?a. 0.16b. 350c. 530d. 14

Answer 1

a. 0.16 (M).

Step-by-step explanation:

What is given?

Volume 1 (V1) = 15.8 mL,

Concentration 1 (C1) = 7.5 M,

Volume 2 (V2) = 743.9 mL.

What do we need? Concentration 2 (C2).

Step-by-step solution:

To solve this problem, we have to use the following formula:

`C_1V_1=C_2V_2.`

Where C indicates concentration and V indicates volume.

We want to find C2, so let's solve for this unknown value and replace the given data in the formula:

`\begin{gathered} C_2=(C_1V_1)/(V_2), \\ \\ C_2=\frac{7.5\text{ M}\cdot15.8\text{ mL}}{743.9\text{ mL}}, \\ \\ C_2=0.159\text{ M}\approx0.16\text{ M.} \end{gathered}`

The answer would be a. 0.16 (M).