These are three separate stoichiometry problems. Here is a sample stoichiometry problem (solved example). Just follow the steps.
http://www.jiskha.com/science/chemistry/stoichiometry.html
The reaction of fluorine with ammonia produces dinitrogen tetrafluoride and hydrogen fluoride.
5 F2(g) + 2 NH3(g) N2F4(g) + 6 HF(g)
(a) If you have 73.7 g NH3, how many grams of F2 are required for complete reaction?
b) How many grams of NH3, are required to produce 5.25 g HF?
(c) How many grams of N2F4 can be produced from 269 g F2?
5 answers
I did follow those steps and they didn't work for the first problem.
Kelsey/Katie -- please do not switch screen names -- especially on the same post!
Do you have the answer? If so I shall try it and see what I obtain. Post your work and I'll look for the error.
I worked it VERY fast with approximate molar masses and came up with an answer close to 412 grams F2 required.