Question

An 13% strength bleach solution is created when 4.5L of water is evaporated away from a 4% bleach solution. Determine the volume of the original 4% bleach solution.

Answer 1

The volume of the original 4% bleach solution was determined to be 6.5 liters, calculated using the conservation of mass and the percentage concentration before and after evaporation.

Step-by-step explanation:

To determine the volume of the original 4% bleach solution, we apply the concept of conservation of mass, since the amount of bleach present remains the same before and after the evaporation. We know that after evaporation, we have a 13% bleach solution. Let the original volume be V.

The amount of bleach in the original solution is 4% of V, which can be written as 0.04V. After 4.5L of water is evaporated, the new volume of the solution is V - 4.5L, and the strength of the solution is now 13%. The amount of bleach is now 13% of (V - 4.5L). The amount of bleach before and after evaporation remains constant, therefore:

0.04V = 0.13(V - 4.5)

To find V, we solve the equation:

0.04V = 0.13V - 0.585

0.585 = 0.13V - 0.04V

0.585 = 0.09V

V = 0.585 / 0.09

V = 6.5L

So, the volume of the original 4% bleach solution was 6.5L.