What volume of 6M HCl and 2M HCl should be mixed to get 2 litres of 3M HCl?

Answer 1

You either do it logically or by maths. Here is the maths solution.

If you need 2 L of 3M then you need a total of 6 moles.

Let x= volume of 6M and y=volume of 2M

so total moles is 6x+2y=6

total volume x+y=2

solve for x and y

I get x=0.5L and y=1.5L