A student takes a sample of KOH solution and dilutes it with 100.00 mL of water. The student determines that the diluted solution is 0.046 M KOH, but has forgotten to record the volume of the original sample. The concentration of the original solution is 2.09 M. What was the volume of the original sample?

2.2mL

Explanation:

First, let us analyse what was given from the question:

C1 = 2.09M

V1 =?

C2 = 0.046M

V2 =100mL

Using dilution formula (C1V1 = C2V2), we can calculate the volume of the original solution as follows:

C1V1 = C2V2

2.09 x V1 = 0.046 x 100

Divide both side by the coefficient of V1 ie 2.09, we have:

V1 = (0.046 x 100) / 2.09

V1 = 2.2mL

there are two significant figures.