How many gallons of pure hydrochloric acid must be added to 10 gallons of a 20% solution to obtain a 50% solution? a) 5 gallons b) 8 gallons c) 10 gallons d) 15 gallons

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asked Sep 7, 2024 157k views

1 Answer

Brett Sutton · Answer 1 · 2024-09-13T07:23:49+0000

To obtain a 50% solution, you will need to add 6 gallons of pure hydrochloric acid to 10 gallons of a 20% solution.

To find the amount of pure hydrochloric acid needed to obtain a 50% solution, we need to set up an equation using the concept of mass balance.

Let x be the amount of pure hydrochloric acid in gallons.

The total volume of the solution will be 10 + x gallons.

The equation will be: 0.2 * 10 + 1 * x = 0.5 * (10 + x)

Simplifying the equation, we get: 2 + x = 5 + 0.5x

Combining like terms, we get: 0.5x = 3

Dividing both sides of the equation by 0.5, we get: x = 6

Therefore, 6 gallons of pure hydrochloric acid must be added to 10 gallons of a 20% solution to obtain a 50% solution.