Answer:
0.06 liters
Explanation:
acid concentration of 65% means that it of 100 units of that solution 65 are acid, and the remaining 35 are water.
so, 100 units are 0.2 liters in this example.
that means that 65/100 × 0.2 = 0.13 liters are acid.
35/100 × 0.2 = 0.07 liters are water
we get a 50% concentration, when we have the same amount of water and acid in the solution (acid is only half of 50% of the solution).
the account of acid remains the same, as we are only adding water.
so, how much water do we need to get from 0.07 liters to 0.13 liters (the same as the already present acid) ?
0.13 - 0.07 = 0.06 liters