Bcalcium, Ca2+[1]
The white precipitates of aluminium and zinc hydroxide dissolve in excess aqueous sodium hydroxide. Ammonium ions give no precipitate.
Biodide, I−[1]
Silver iodide is yellow. Silver chloride is white, sulfate is tested with barium nitrate, and any carbonate is removed by the nitric acid.
Cchlorine[1]
Chlorine is acidic and also bleaches. Ammonia turns red litmus blue, carbon dioxide is odourless, and sulfur dioxide is tested with acidified potassium manganate(VII).
A red-brown precipitate, insoluble in excess. [1]
Acidify with dilute nitric acid, then add aqueous barium nitrate: a white precipitate forms. [1]
Hold a lighted splint at the mouth of the tube: it is extinguished with a pop. [1]
Aqueous ammonia (in excess). [1]
Dacidified potassium manganate(VII) turns from purple to colourless[1]
Sulfur dioxide turns acidified potassium manganate(VII) from purple to colourless. A is the test for oxygen and B is the test for chlorine.
Ciron(II) nitrate[1]
The green precipitate shows iron(II) ions. No effervescence with nitric acid means no carbonate, and ammonia with aluminium foil shows nitrate ions.
Dsodium nitrate[1]
No ammonia before the aluminium is added, so there are no ammonium ions. Ammonia after adding aluminium shows nitrate ions.
Badd aqueous sodium hydroxide and warm[1]
Only ammonium nitrate gives ammonia when warmed with aqueous sodium hydroxide. With aluminium foil, both nitrates would give ammonia.
B3 only[1]
Aqueous ammonia gives no change with either. Barium nitrate gives a white precipitate with both (barium sulfate and barium carbonate). Only hydrochloric acid gives effervescence, with the carbonate.
Ccalcium nitrate[1]
A white precipitate insoluble in excess shows calcium ions. Ammonia after adding aluminium shows nitrate ions.
Add aqueous ammonia dropwise, then in excess: a green precipitate forms which is insoluble in excess. [1]
Fe2+(aq) + 2OH−(aq) → Fe(OH)2(s): correct ionic equation [1]
Correct state symbols [1]
A light blue precipitate. [1]
The light blue precipitate dissolves in excess aqueous ammonia, giving a dark blue solution. [1]