He concentration of pb2+ in a commercially available standard solution is 1.00 mg/ml. what volume of this solution should be diluted to 5.0×102 ml to produce a solution in which the concentration of pb2+ is 0.055 mg/l?

This can be directly solved using the formula:

C1 V1 = C2 V2

where C is concentration and V is volume

1.00 mg/ml * V1 = 0.055 mg/1000 ml * (5.0 x 10^2 ml)

V1 = 0.0275 ml

So 0.0275 ml is needed to be diluted to 5.0 x 10^2 ml

introduction of a drug directly into the respiratory tract is a form of inhalation administration.

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