Question

6. Solid ammonium dichromate (relative molecular mass=262) on heating decomposes as follows
(NH4)2Cr2O7-N2 + Cr2O3 + 4H20
(a) Calculate the volume of nitrogen at STP, that will be evolved when 31.5 g ammonium
dichromate is heated, and
(b) The mass of chromium (III) oxide formed at the same time
(H = 1, N = 14,0 = 16, Cr = 52).​

Answer 1

The following is the chemical reaction (NH4)2Cr2O7(s) on heating decomposes to Cr2O3(s) + N2(g) + 4H2O(g)

a—the volume of nitrogen at STP, that will be evolved when 31.5 g ammonium is 2.80 litres

b—The mass of chromium (III) oxide formed at the same time is 27.0 grams