Question

A sample of ammonium nitrate when heated yields 8.96 litres of steam (measure at STP).

\[\ce{NH4NO3 -> N2O + 2H2O}\]

1. What volume of dinitrogen oxide is produced at the same time as 8.96 litres of steam?
2. What mass of ammonium nitrate should be heated to produce 8.96 litres of steam? (Relative molecular mass of ammonium nitrate is 80).
3. Determine the percentage of oxygen in ammonium nitrate (O = 16).

Answer 1

(i) \[\ce{\underset{1 vol.}{NH4NO3} ->[\Delta] \underset{2 vol.}{N2O_{(g)}} + 2H2O_{(g)}}\]

Volume of N₂O produced = `1/2 xx 8.69`

= 4.48 L

(ii) \[\ce{\underset{1 mole}{NH4NO3}->[\Delta]\underset{2 moles}{N2O} + 2H2O}\]

1 mole of NH₄NO₃ has mass = 14 + 4 + 14 + 48

= 80 g

44.8 L of steam at STP is obtained from NH₄NO₃ = 80 g

∴ 8.96 L of steam will be liberated by = `80/44.8 xx 8.96`

= `(80 xx 2)/10`

= 16 g

(iii) % age of oxygen in NH₄NO₃ = `48/80 xx 100/1`

= 60%