How does dilution affect molarity?

1 Answer

Diluting a sample will reduce the molarity.

For example if you have 5mL of a 2M solution which is diluted to a new volume of 10mL the molarity will be reduced to 1M.

To solve a problem like this one you'll apply the equation:
#M_1V_1# = #M_2V_2#

This would be solved to find
#M_2# = (#M_1V_1#)/#V_2#

#M_2# = (5mL*2M)/10mL

Here is a video that describes this process and provides another example of how to calculate the change in molarity when a solution is diluted.

slideplayer.com