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A soil sample from an urban backyard in Jersey City contaminated

with Lead(Pb) has a weight of 5 lb. It was analyzed for Pb content
and the concentration. of Pb found to be 500 ppm. What is the total

User Leon Gaban
by
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1 Answer

3 votes

Answer:

0.0025 lbs lead in 5 lb of soil

Step-by-step explanation:

The lead is found at a concentration of 500 ppm (parts per million). We can write this as:

(500 lb Pb)/(1,000,000 lb soil) or (500 lb Pb)/(10^6 lb soil))

5 pounds of soil would therefore contain:

(5 lb soil)*(500 lb Pb)/(10^6 lb soil))

The units "lb soil" from cancel, leaving only pounds of lead.

(5 lb soil)*(500 lb Pb)/(10^6 lb soil))

(5)*(500 lb Pb)/(10^6)) = 0.0025 lbs lead

User Darius Bogdan
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