# How does dilution affect molarity?

Apr 25, 2014

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:
${M}_{1} {V}_{1}$ = ${M}_{2} {V}_{2}$

This would be solved to find
${M}_{2}$ = (${M}_{1} {V}_{1}$)/${V}_{2}$

${M}_{2}$ = (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.