Question

A 1 liter solution was diluted to a molarity of 2 M by bringing the volume up to 4 liters. What was the initial molarity of the solution?

Answer 1

Answer:

8.0 mol/L

Explanation:

To do this problem you need to use C₁V₁=C₂V₂. C=concentration and V=volume. (Note: you dont want to use M₁V₁=M₂V₂ because this is measuring mass not concentration).

So, V₁= 1.0L

C₂=2 Mol/L

V₂= 4 L

C₁ is unknown.

you would plug this equation in like this:

(C₁)(1.0 L)=(2.0 Mol/L)(4.0L).

Do algebra to get C₁ alone.

C₁=$\frac{(2.0 mol/L)(4.0L)}{1.0L} =8.0 mol/L$

The liters cancel out and you are left with mol/L or M

I hope this helps! good luck :)