Older MCQs might not have the typical A, B, C,
D
choices. They
have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such
combinations to the answer.
A
1, 2 and 3 are correct
B
1 and 2 only are correct
C
2 and 3 only are correct
D
1 only is correct
Describe tests to identify the anions: (a) carbonate, ( CO_3^{2-} ), by reaction with dilute acid and then testing for carbon dioxide gas (b) chloride, ( Cl^- ), bromide, ( Br^- ), and iodide, ( I^- ), by acidifying with dilute nitric acid then adding aqueous silver nitrate (c) nitrate, ( NO_3^- ), reduction with aluminium foil and aqueous sodium hydroxide and then testing for ammonia gas (d) sulfate, ( SO_4^{2-} ), by acidifying with dilute nitric acid and then adding aqueous barium nitrate (e) sulfite, ( SO_3^{2-} ), by reaction with acidified aqueous potassium manganate(VII)
Describe how paper chromatography is used to separate mixtures of soluble colourless substances, using a suitable solvent and a locating agent Knowledge of specific locating agents is not required
