Answer:- 0.0002 ppm
Solution:- 1 ppm is one mg of solute per liter of solvent or one kg of solvent.
It asks to convert [tex]\frac{20\mu g}{dL}[/tex] pb in blood to ppm. density of blood is [tex]\frac{1g}{mL}[/tex] .
Let's convert micrograms to milligrams and also calculate the mass of blood from it's given density. The set up could be made using dimensional analysis and doing unit conversions as:
First the set up for the conversion of micrograms of Pb to milligrams:
[tex]\frac{20\mu g}{dL}(\frac{0.001mg}{1\mu g})[/tex]
= [tex]\frac{0.02mg}{dL}[/tex]
Now, the set up for converting dL of blood to kg using it's given density and unit conversion from dL to mL as:
[tex]\frac{0.02mg}{dL}(\frac{0.01dl}{1mL})(\frac{1mL}{1g})(\frac{1000g}{1kg})[/tex]
= 0.200 ppm