J.R. S. answered 05/26/20
Ph.D. University Professor with 10+ years Tutoring Experience
1) Find the limiting reactant:
moles N2 = x
moles H2 = y
Divide x by 1 and y by 3 and whichever is smaller is the limiting reactant
Theoretical yield = moles limiting reactant x moles 2 mol NH3/mol LR x molar mass NH3 = g NH3
Percent yield = actual/theoretical (x100%) = 17.8 g / theoretical (x100%) = answer