If 40.0 mL of a 3.0x10^(-5) solution is diluted to 100 mL, what is the resulting concentration?

1 Answer
Aug 26, 2016

M_f=1.2xx10^(-5)M

Explanation:

When a solution is diluted, the number of mole of particles in the solution does not change.

The relationship between the number of mole n and the molarity M is the following:

M=n/V=>n=MxxV

where, V is the volume of the solution.

If we consider that initially the volume and the molarity are:

M_i=3.0xx10^(-5)M

V_i=40 mL

What would be the final molarity M_f=? when the final volume is V_f=100mL?

since the number of mole does not change, we can write:

M_ixxV_i=M_fxxV_f

=>M_f=(M_ixxV_i)/(V_f)=(3.0xx10^(-5)Mxx40cancel(mL))/(100cancel(mL))=1.2xx10^(-5)M

Here is a video that discusses the solution preparation and dilution:
Lab Demonstration | Solution Preparation & Dilution.