Question

Hydrazine, N2H4 reacts with H2SO4 2 N2H4 (aq) + H2SO4(aq) → 2 N2H5+(aq) + SO4(aq) What mass of hydrazine reacts with 250 ml of 0.225 M H2SO4?

Answer 1

Answer

Mass of N₂H₄ = 3.605085 grams

Explanation

Given:

Molarity of H₂SO₄ = 0.225 M

Volume of H₂SO₄ = 250 mL = 0.250 L

Equation:

$2N_2H_{4(aq)}+H_2SO_{4(aq)}\rightarrow2N_2H_{5(aq)}+SO_{4(aq)}$

What to find:

The mass of hydrazine, N₂H₄.

Step-by-step solution:

To find the mass of hydrazine first we need to find the moles of hydrazine from the moles of sulfuric acid using given data and given balanced equation above.

Moles of H₂SO₄ in 0.225 M with 250 mL is calculated as follows:

$\begin{gathered} \text{Molarity }=\frac{Moles}{Volume\text{ in L}} \\ So\text{ Moles of H}_{2}SO_{4}=\text{Molarity }\times Volume\text{ in L} \\ \text{Moles of H}_{2}SO_{4}=0.225\text{ M }\times0.250\text{ L }=0.05625\text{ mol} \end{gathered}$

Now we can determine the moles of hydrazine by comparing the moles with the balanced equation for the reaction.

From the balanced equation; 1 mole of H₂SO₄ reacts with 2 moles of N₂H₄,

So 0.05625 mole of H₂SO₄ will reacts with:

$\frac{0.05625\text{ mol }H_2SO_4\times2\text{ mol }N_2H_4\text{ }}{1\text{ }mol\text{ }H_2SO_4}=0.1125\text{ moles of }N_2H_4$

Now using Number of moles = Mass/molar mass, we can then calculate the mass of hydrazine as follows:

From the Periodic Table:

Molar mass of hydrazine = 32.0452 g/mol

Hence, Mass of hydrazine = Number of moles of hydrazine x Molar mass of hydrazine.

Mass of N₂H₄ = 0.1125 mol x 32.0452 g/mol

Mass of N₂H₄ = 3.605085 grams