Question

Air bags in cars operate according to the reaction below. How many grams of nitrogen gas are produced during the decomposition of 3.25 g Na3N?

Answer 1

Answer : The mass of nitrogen gas produced during the decomposition of
`Na_3N` are, 0.546 grams.

Solution : Given,

Mass of
`Na_3N` = 3.25 g

Molar mass of
`Na_3N` = 83 g/mole

Molar mass of
`N_2` = 28 g/mole

First we have to calculate the moles of
`Na_3N`.

`\text{ Moles of }Na_3N=\frac{\text{ Mass of }Na_3N}{\text{ Molar mass of }Na_3N}=(3.25g)/(83g/mole)=0.039moles`

Now we have to calculate the moles of
`MgO`

The balanced chemical reaction will be,

`2Na_3N\rightarrow N_2+6Na`

From the balanced reaction we conclude that

As, 2 mole of
`Na_3N` react to give 1 mole of
`N_2`

So, 0.039 moles of
`Na_3N` react to give
`(0.039)/(2)=0.0195` moles of
`N_2`

Now we have to calculate the mass of
`N_2`

`\text{ Mass of }N_2=\text{ Moles of }N_2* \text{ Molar mass of }N_2`

`\text{ Mass of }N_2=(0.0195moles)* (28g/mole)=0.546g`

Therefore, the mass of nitrogen gas produced during the decomposition of
`Na_3N` are, 0.546 grams.