qualitative analysis o level syllabus

What is the product formed when a few drops of aqueous sodium hydroxide is added to aluminium ion, Al3+

A white ppt is formed

What is the product formed when a few drops of aqueous sodium hydroxide is added to Zinc ion, Zn2+

A white ppt of zinc hydroxide is formed

What is the product formed when a few drops of aqueous sodium hydroxide is added to Calcium ion, Ca2+

A white ppt of calcium hydroxide is formed

What is the product formed when a few drops of aqueous sodium hydroxide is added to Ammonium ion, NH4+

No ppt

What is the product formed when a few drops of aqueous sodium hydroxide is added to Copper(II) ions, Cu2+

A light blue ppt of Copper(II) hydroxide is formed

What is the product formed when a few drops of aqueous sodium hydroxide is added to Iron (II) ion, Fe2+

A green precipitate of iron (II) hydroxide is formed

What is the product formed when a few drops of aqueous sodium hydroxide is added to Iron (III) ion, Fe3+

A red-brown ppt of iron(III)hydroxide is formed

What is the product formed when a excess aqueous sodium hydroxide is added to aluminium ion

White ppt dissolves to form a Colourless solution

What is the product formed when excess of aqueous sodium hydroxide is added to Zinc ion

White ppt dissolves into a Colourless solution

What is the product formed when excess of aqueous sodium hydroxide is added to Calcium ion

Ppt is insoluble in excess, hence remains white

What is the product formed when excess aqueous sodium hydroxide is added to Copper(II)ions

The light blue ppt remains light blue as it is insoluble in excess sodium hydroxide

What is the product formed when excess aqueous sodium hydroxide is added to Iron (II) ions

The green ppt is insoluble in excess sodium hydroxide so it remains green but turns brown on standing due to oxidation of Fe2+ into Fe3+ due to reaction with air

What is the product formed when excess aqueous sodium hydroxide is added to Iron(III) ion

Red-brown precipitate remains red-brown as it is insoluble in excess NaOH

What is the product formed when a a few drops of aqueous ammonia is added to aluminium ions

A white precipitate of aluminium hydroxide is formed

What is the product formed when a a few drops of aqueous ammonia is added to Zinc ion

A white ppt of zinc hydroxide is formed

What is the product formed when a a few drops of aqueous ammonia is added to calcium ions

No ppt

What is the product formed when a a few drops of aqueous ammonia is added to copper(II) ions

A light blue ppt of copper(II)hydroxide is seen

What is the product formed when a a few drops of aqueous ammonia is added to iron(II) ions

A green ppt of iron(II)hydroxide is seen

What is the product formed when a a few drops of aqueous ammonia is added to Iron (III) ion

A red-brown ppt is seen

What is the product formed when excess aqueous ammonia is added to aluminium ion

Initially formed white aluminium hydroxide ppt remains white as it is insoluble in excess ammonia

What is the product formed when excess aqueous ammonia is added to Zinc ion

Initially formed white zinc hydroxide ppt dissolves to form a Colourless solution as zinc hydroxide is soluble in excess aqueous ammonia

What is the product formed when excess aqueous ammonia is added to copper (II) ion

Light blue ppt formed dissolves in excess to form a dark blue solution

What is the product formed when excess aqueous ammonia is added to Iron( II) ion

Initial green ppt of iron (II) hydroxide formed remains green as its insoluble in excess aqueous ammonia and turns brown on standing

What is the product formed when excess aqueous ammonia is added to iron (III) ion

Initial red-brown precipitate of iron(III) hydroxide remains red-brown

What’s the test and observations for positive test for presence of carbonate ion?

Add dilute acid: effervescence is observed then bubble gas given off into limewater to form a white precipitate of calcium carbonate due to CO2 being evolved

What’s the test and observations for positive test for presence of chloride ion?

Add dilute nitric acid and aqueous silver nitrate to form a white ppt of silver chloride which is insoluble in water

What’s the test and observations for positive test for presence of Iodide ion

Add dilute nitric acid and aqueous silver nitrate, a yellow silver iodide ppt is formed as AgI is not soluble in water

What’s the test and observations for positive test for presence of Sulfate ion

Add dilute nitric acid and aqueous barium nitrate to form a white ppt of barium sulfate as it is insoluble in water

What’s the test and observations for positive test for presence of Nitrate ion?

Add aqueous sodium hydroxide and a piece of aluminium metal then warm the mixture carefully. Effervescence is observed. Then the gas given off, ammonia should turn damp red litmus paper blue