Question

A chemist has 0.5 liters of an acid solution whose acid concentration is 30%. How many liters of pure water should be added to lower the concentration to 25%?

Answer 1

@robtoby

Answer 2

I'm not sure if I did this right, but I did 30% of 0.5 is 0.15 and 25% of 0.5 is 0.125. So I subtracted those two decimals and got 0.025. This is the only way I could think of. I even looked this up on google, but found nothing. I'm hoping I did this right..

Answer 3

You are not right @jmlovett2000

Answer 4

K

Answer 5

The idea is this: Find the amount of acid in the whole solution. You can do this as you know the litres of the solution and the proportion of the solution which is acid. Then you need to find how much water in total you need to make the proportion of acid in the solution 25%. Is that starting to make sense for you?

Answer 6

Yes, is the answer 0.1

Answer 7

Yes :)

Answer 8

thanks