A sample of drinking water was tested for Pb2 and was found to have a Pb2 concentration of 17.50 ppb. A 9.00 mL sample of the drinking water was spiked with 1.00 mL of a 2.29 ppb Pb2 standard. Analysis of the spiked sample gave a concentration of 15.93 ppb Pb2 . Find the percent recovery of the spike.

Explanation:

From the question we are told that:

Concentration

Volume

Spike Volume

spike Conc

Analysis Conc

Generally the equation for  percent recovery is mathematically given by

Where

Concentration of spiked sample C_s'

Concentration of unspiked sample C_1'

Concentration of spike sample C_2'

Therefore

the answer is d : ) have a good da