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

Mass of N₂H₄ = 3.605085 grams

Step-by-step 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 }* Volume\text{ in L} \\ \text{Moles of H}_(2)SO_(4)=0.225\text{ M }*0.250\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*2\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