How much stock solution of hydrogen peroxide 8% will you need to make 320ml of hydrogen peroxide 2% solution?

To determine how much stock solution of hydrogen peroxide 8% you will need to make 320ml of hydrogen peroxide 2% solution, we can use the formula:

(C1 × V1) = (C2 × V2)

Where:
C1 = concentration of the stock solution (%)
V1 = volume of the stock solution (ml)
C2 = concentration of the desired solution (%)
V2 = volume of the desired solution (ml)

Plugging in the known values:
C1 = 8%
V1 = ?
C2 = 2%
V2 = 320ml

We want to solve for V1, so our equation becomes:
(8% × V1) = (2% × 320ml)

To isolate V1, we can divide both sides of the equation by 8%:
V1 = (2% × 320ml) / 8%

Now, let's do the calculations:
V1 = (2% × 320ml) / 8%
V1 = 6.4ml

Therefore, you will need 6.4ml of the hydrogen peroxide 8% stock solution to make 320ml of hydrogen peroxide 2% solution.