Question

How many ml of a 4% stock solution is needed to compound an order for 100 ml of 0.04% solution is distilled water?

a. 1 ml
b. 2 ml
c. 4 ml
d. 8 ml

Answer 1

To prepare 100 mL of a 0.04% solution from a 4% stock solution, 1 mL of the stock solution is needed, using the dilution formula M1V1 = M2V2 and solving for the required volume. The correct answer is option: a. 1 ml

Step-by-step explanation:

To determine how many mL of a 4% stock solution is needed to compound an order for 100 mL of a 0.04% solution in distilled water, we can use the dilution formula M1V1 = M2V2, where M1 is the concentration of the stock solution, V1 is the volume of the stock solution needed, M2 is the concentration of the diluted solution, and V2 is the final volume of the solution.

Here, M1 is 4%, M2 is 0.04%, and V2 is 100 mL. Plugging in these values, we get:

(4%)V1 = (0.04%)(100 mL)

First, to make the equation easier to solve, it is helpful to convert the percentages into a decimal form:

4% = 0.04 and 0.04% = 0.0004

So now the equation becomes:

(0.04)V1 = (0.0004)(100 mL)

Now, we isolate V1 by dividing both sides of the equation by 0.04:

V1 = (0.0004)(100 mL) / 0.04

V1 = 0.4 mL

Thus, 1 mL of the 4% stock solution is needed to prepare 100 mL of a 0.04% solution, which means the correct answer is option a. 1 mL.