Dilution of Solutions

We learned about how to dilute solutions

Diluting is when water is added to a solution, which increases volume but decreases concentration of the solution(molarity)

Here is the formula needed to solve these dilution problems:

(Molarity 1) (Volume(in L)1) = (Molarity 2) ( Volume(in L) 2)

or M1L1= M2L2

Here are some examples:

1. 20.0 ml of 0.200 M NaOH solution is diluted to a final volume of 100.0 mL. Calculate the new concentration.

All you do is plug in the numbers.

20.0 mL is initial volume
0.200 M is initial molarity
100.0 mL is final volume

(0.200 M) (0.02 L) = (M2) ( 0.1 L)

= 0.200x 0.02/0.1= 0.04 M

2.  150.0 ml of 0.025 M NaOH solution is added to 150.0 mL of water. Calculate new molarity.

150.0 mL = initial volume
0.025M = initial molarity
Now, final volume is 150 mL + 150 mL = 300 mL

M1L1=M2L2

(0.025 M) (0.15 L) = (M2) ( 0.3 L)

0.025 x 0.15/ 0.3= 0.012 M


http://www.youtube.com/watch?v=0dRwHZCDBp4

Extra help!