Question

In one of the routine analyses, Dr Entropy found that the concentration of phosphate had increased from 0.0090 mg/L to 0.220 mg/L. This will require a lengthy investigation and detailed report into the causes. Being the master of disorder, he considers an act of serious scientific misconduct - diluting the sample to reduce phosphate concentration to the maximum allowable level of 0.100 mg/L, and hoping that no-one notices.
If the volume of the original sample with concentration 0.220 mg/L is 10.0 mL, what should be the final volume of solution in order to dilute it to 0.100 mg/L?

Answer 1

Answer:

The final volume should be 22 mL

Explanation:

For this problem, we will use the dilution equation:

C1*V1 = C2*V2

Step 1: Data given

with C1 = the initial concentration C1 = 0.220 mg/L

with V1 = the initial volume = 10 mL = 10 * 10^-3 L

with C2 = the final concentration = 0.100 mg/L

with V2 = the final volume = TO BE DETERMINED

Step 2: Calculating the final volume

C1*V1 = C2*V2

0.220 mg/L * 10*10^-3 L = 0.100 mg/L * V2

V2 = (0.220 mg/L * 10*10^-3 L) / 0.100 mg/L

V2 =0.022 L = 22 mL

The final volume should be 22 mL