For the balanced reaction:
N2H4 + 2H2O2 = N2 + 4H2O
12.0 g N2H4 is reacted with 23.0 g H2O2. Which is the limiting reactant?
Let's calculate the number of moles for the two given reactants, because only the molar ratio of the reactants can be compared to the stoichiometric ratio from the equation.
To get the number of moles, we need to divide the weight of the reactants by their molecular weight.
Moles of N2H4: 12.0 g / 32.06 g/mol = 0.374 mole N2H4
Moles of H2O2: ...