Reactions of Period 3 elements with water and oxygenAQA A-Level Chemistry: Mind map

Exam questions on Reactions of Period 3 elements with water and oxygen

1. A teacher demonstrates the reactions of small pieces of sodium and of magnesium ribbon with cold water, in separate troughs, adding universal indicator to each.
   Explain why sodium reacts more vigorously with water than magnesium does.2 marks
2. A student heats small samples of magnesium ribbon, aluminium powder, silicon and sulfur in separate combustion spoons in oxygen, in a fume cupboard.
   Write equations for the reactions of aluminium and of silicon with oxygen.2 marks
3. A student compares how readily the Period 3 elements react with oxygen. She notes that sodium and magnesium burn vigorously, that phosphorus burns to give white fumes, and that aluminium foil stays unreactive in air at room temperature even though aluminium is a reactive metal.
   Write an equation for the burning of phosphorus in excess oxygen, state the oxidation state of phosphorus in the product and state what is seen.3 marks