Choose from the following compounds to answer the questions. NH4Cl BaSO4 KI K2SO3 Mg(NO3)2 NaOCOCH3 Na2CO3 Na3PO4 ZnSO4 Each compound may be used once, more than once or not at all. State which compound:

1. (a)reacts with dilute nitric acid to form a gas that turns limewater milky[1]
2. (b)reacts with warm aqueous sodium hydroxide to form a gas that turns damp red litmus paper blue[1]
3. (c)reacts with dilute hydrochloric acid to give a gas that decolourises acidified potassium manganate(VII)[1]
4. (d)is prepared using a precipitation reaction[1]
5. (e)contains an anion with a charge of –3[1]
6. (f)is used to test for an oxidising agent.[1]