I think this is stoichiometry? ?

Question

Lead is a heavy metal that remains in the bloodstream, causing mental retardation in children. It is believed that 3.0 x 10-7g of lead in 1.00mL of blood is a health hazard. For this amount of lead

a. How many atoms of lead are there is 1.0mL of a child’s blood?

b. How many moles of lead are in 1.00L of blood?

Any help would be great, i think the answer to the first one is 1.7x10^14. But I'm not positive.

Answer 1

this is not stoichiometry, it's just an conversion of units

i don't have a calculator on me so i won't bother with the numerical value but this is how you do it:

a. Find molecular mass of lead Pb... 3.0x10^07 divided by your molecular mass. that's your moles (so here's your answer for B). THen take that and times 6.022x10^23

because each mole there's 6.022x10^23 molecule or atoms...  

Answer 2

3.0 x 10-7g of lead  @ 6.022e23 atoms / 207.2 grams  =

your first answer: 8.7e14 atoms

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b. How many moles of lead are in 1.00L of blood

@  3.0 x 10-7g of lead in 1.00mL , there are  3.0 x 10-4g of lead in 1.00 L

3.0 x 10-4g of lead @ 1 mole / 207.2 grams = 1.448e-6 moles

Your next answer: 1.4e-5 moles