Question

what is the final molarity of a dilute solution of NaOH that is prepared by pipetting 5.00 mL of 7.00 M NaOH into a 100mL volumetric flask and diluting with water

Answer 1

Answer:

$M_{diluted}=0.35M$

Explanation:

Hello,

In this case, since in a dilution process the moles of the solute must remain unchanged, we use the volumes and molarities as shown below:

$M_{diluted}V_{diluted}=M_{concentrated}V_{concentrated}$

Clearly, the concentrated solution is 7.00M and the diluted solution is unknown, thus, the concentration of the diluted solution after the dilution to 100 mL is:

$M_{diluted}=\frac{M_{concentrated}V_{concentrated}}{V_{diluted}} =\frac{7.00M*5.00mL}{100mL}\\ \\M_{diluted}=0.35M$

Best regards.