Question

2N2H4 + N2O4 → 3N2 + 4H2O

How many grams of N2H4 will be consumed by 92 g of N2O4?





16 g

128 g

64 g

32 g

Answer 1

With N2O4's molar mass of 92 grams/mole, there is 1 mole of N2O4 being used.
For every one mole of N2O4 used, two moles of N2H4 are used.
2 moles of N2H4 times the molar mass of N2H4 (32g/mol)
2 moles * (32 grams/mole) = 64 grams

Answer 2

Answer : The amount of
`N_2H_4` will be, 64 g

Solution : Given,

Mass of
`N_2O_4` = 92 g

Molar mass of
`N_2O_4` = 92 g/mole

Molar mass of
`N_2H_4` = 32 g/mole

First we have to calculate the moles of
`N_2O_4`.

`\text{Moles of }N_2O_4=\frac{\text{Mass of }N_2O_4}{\text{Molar mass of }N_2O_4}=(92g)/(92g/mole)=1mole`

Now we have to calculate the moles of
`N_2H_4`.

The balanced chemical reaction is,

`2N_2H_4+N_2O_4\rightarrow 3N_2+4H_2O`

From the balanced reaction, we conclude that

1 mole of
`N_2O_4` react with 2 moles of
`N_2H_4`

and from the calculated moles,

1 mole of
`N_2O_4` react with 2 moles of
`N_2H_4`

Now we have to calculate the mass of
`N_2H_4`

`\text{Mass of }N_2H_4=\text{Moles of }N_2H_4* \text{Molar mass of }N_2H_4`

`\text{Mass of }N_2H_4=(2mole)* (32g/mole)=64g`

Therefore, the amount of
`N_2H_4` will be, 64 g