A solution contains 80% acid. How much water must be added to 20 liters of this solution to make acid 50%?
Show answer & explanation
Correct answer: A
Explanation
Given:
Solution = 20 L
Acid = 80%
Final Acid Concentration = 50%
According to the formula:
Amount of Acid = (Percentage / 100) × Total Solution
Initial Acid = (80 / 100) × 20 = 16 L
Let the amount of water added be x L.
New Total Solution = (20 + x) L
Acid Percentage = 50%
16 / (20 + x) = 50 / 100
16 / (20 + x) = 1 / 2
32 = 20 + x
x = 12
Water added = 12 L