Determine how many grams of n2 are produced from the reaction of 8.37 g of h2o2 and 5.29 g of n2h4.

N₂H₄  +  2H₂O₂    →   N₂  +  4H₂O

mol = mass ÷ molar mass

If mass of hydrazine (N₂H₄)  = 5.29 g 
then mol of hydrazine           = 5.29 g ÷ ((14 ×2) + (1 × 4))
                                              = 0.165 mol

mole ratio of hydrazine to Nitogen is     1   :  1
  ∴ if moles of hydrazine = 0.165 mol
     then moles of nitrogen = 0.165 mol

Mass = mol × molar mass

Since mol of nitrogen (N₂)  = 0.165
then mass of hydrazine      = 0.165 × (14 × 2)
                                           = 4.62 g