How many pounds of a 5% bleach solution are needed to obtain 1 pound of chlorine?

• A. 2 pounds
• B. 12 pounds
• C. 20 pounds
• D. 22 pounds

Answer: (C)

To determine how many pounds of a 5% bleach solution are required to yield 1 pound of chlorine, it's important to understand the concentration of the bleach solution. A 5% bleach solution means that 5% of the solution's weight is pure chlorine.

To find out how much total solution contains 1 pound of chlorine, you can use the formula for concentration:

[

\text{Amount of chlorine} = \text{Total weight of solution} \times \text{Concentration}

]

In this case, you know that the concentration is 5%, or 0.05 in decimal form. You can set up the equation as follows:

[

1 \text{ pound of chlorine} = \text{Total weight of solution} \times 0.05

]

Now, rearranging the equation to solve for the total weight of the solution gives:

[

\text{Total weight of solution} = \frac{1 \text{ pound of chlorine}}{0.05}

]

Calculating this gives:

[

\text{Total weight of solution} = 20 \text{ pounds}

]

Therefore, to obtain 1 pound of chlorine, you need to use 20 pounds