What is the mass of potassium iodide (166.00 g/mol) that yields 0.500g of lead (II) iodide (461.0 g/mol) precipitate?

(a): __Pb(NO3)2(ag) + 2__ KI(s) = ___PbI2(s) + 2KNO3(aq)

(b): Considering the limiting reactant, what mass of cobalt (III) sulfide (214.07 g/mol) is produced from 0.750g of cobalt and 0.350g of sulfur? If 0.565g is produced what is the percent yield?

2 Co(s) + 3 S(s) = Co2S3(s)

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(How many moles of ammonia contain 6.59 x 10^21 NH3 molecules?)

How many H atoms are in the previous example?

- That was the problem I have already answered the question in parenthesis, however, I cannot understand what my professor is asking me about how many H atoms there are. Do I just say how many H atoms there are based on that problem? Do I have to convert molecules to atoms given the specific number of H atoms she wants? That is the only thing I can think of.