4 A student is preparing a sample of sodium nitrate,
NaNO3.
She mixes 17 g of sodium oxide with an excess of nitric
acid. The equation for the reaction is:
Na₂O + 2HNO3 → 2NaNO3 + H₂O
Relative atomic masses (A): Na = 23, O=16, N = 14, H =
1.
a Calculate the number of moles in 17 g of sodium
oxide. (2 marks)
b Calculate the maximum mass of sodium nitrate that
can be produced in this reaction.
(3 marks)
5 Aluminium and iron oxide (Fe2O3) react together to
produce aluminium oxide (Al2O3). The equation for the
reaction is:
2AI + Fe₂O3 → Al₂O3 + 2Fe
Calculate the mass of iron that is produced by reacting 20
g of iron oxide with an excess of aluminium.
Relative atomic masses (A): Al = 27, O=16, Fe = 56. (4
marks)