How much water would you add to 12 M HCl to make 650 mL of 1.5 M HCl? Hint: This is a dilution problem

Answer 1

you are diluting it 12/1.5 times, or 8 times.

8 times means one part original, seven parts water.

well, 8 parts makes 650ml, so one part is 650/8=81.25 ml of acid, then
7 parts water (7*81.25 or 650-81.25) 569ml

Your teacher is too easy.

Answer 2

Agreed it is a dilution problem. There is however a problem with the wording as it is not good practice to add water to the concentrated acid.

if we use

M1V1=M2V2

then

12V1=650x1.5

to find the initial volume (V1) of the 12 M needed

The volume of water to which the 12 M HCl is added is then 650 ml-V1.

Answer 3

Bob types faster than me!!