Problema Solution

A chemistry student needs a 20% solution of Hydrocloric Acid. He has a 40% solution. How many ml of water does he need to add to 10ml of the 40% solution to get the 20% solution?

Answer provided by our tutors

40% hcl solution

4ml in 10ml of solution

for 20 percent we need

4 ml in 20 ml of solution

hence we need to add 10 ml water