Question

Solid ammonium dichromate decomposes as:

\[\ce{(NH4)2Cr2O7 -> N2 + Cr2O3 + 4H2O}\]

If 63 g of ammonium dichromate decomposes. Calculate the volume of N₂ evolved at STP.

Answer 1

Solid ammonium dichromate decomposes as:

\[\ce{(NH4)2Cr2O7 -> N2 + Cr2O3 + 4H2O}\]

252 g of ammonium dichromate gives 22.4 dm³ of N₂

63 g of ammonium dichromate gives `(63 xx 22.4)/252`

= 5.6 L

Answer 2

The volume of N₂ evolved at STP = `22.4/4`

= 5.6 litres