Question

Hydrazine (n2h4) is used as rocket fuels. it reacts with oxygen to form nitrogen and water. write the balanced equation for this reaction. n2h4 + o2 → n2 +2h2o how many liters of n2 at stp form when 100g of n2h4 reaction with 100g of o2? how many grams of the excess reagent remain after the reaction?

Answer 1

The answer is: volume of nitrogen is 70L.

Chemical reaction: N₂H₄ + O₂ → N₂ + 2H₂O.

m(N₂H₄) = 100 g; mass of hydrazine.

M(N₂H₄) = 32 g/mol; molar mass of hydrazine.

n(N₂H₄) = m(N₂H₄) ÷ M(N₂H₄).

n(N₂H₄) = 100 g ÷ 32 g/mol.

n(N₂H₄) = 3.125 mol; amount of hydrazine.

m(O₂) = 100 g; mass of oxygen.

M(O₂) = 32 g/mol; molar mass of oxygen.

n(O₂) = 100 g ÷ 32 g/mol.

n(O₂) = 3.125 mol; amount of oxygen.

From chemical reaction: n(O₂) : n(N₂) = 1 : 1; n(O₂) = n(N₂).

n(N₂) = 3.125 mol; amount og nitrogen gas.

V(N₂) = n(N₂) · Vm.

Vm = 22.4 L/mol; molar volume.

V(N₂) = 3.125 mol · 22.4 L/mol.

V(N₂) = 70 L.

There is not excess reagent, because hydrazine and oxygen are all used in chemical reaction.