If you have 5 ml of a 1:20 dilution and add 5 more ml, what dilution do you now have?

Question

Quizplus · Accepted Answer

1:20 dilution means that 1 part of the original solution is diluted in 20 parts of diluent. If you add 5 more ml of diluent, the total volume becomes 10 ml. The original 5 ml of 1:20 dilution contains 1/20 of the original solution, so the total amount of original solution in the 10 ml is 1/20 * 5 ml = 1/4 of the original solution. Therefore, the new dilution is 1:40.

If You Have 5 Ml of a 1:20 Dilution and Add