12 3 identification of ions and gases

An anion is a negatively charged ion.

The test and result for bromide ions is:

The formula of a carbonate ion is CO32-.

The test for carbonate ions is:

The test and result for iodide ions is:

True. Chloride ions give a white precipitate with silver nitrate solution.

False. To test for sulfate ions, dilute nitric acid and acidified barium nitrate are used.

The white precipitate formed during a positive test for sulfate ions is barium sulfate.

The state symbol for the precipitate of silver bromide is s.

The formula of the precipitate formed when silver nitrate solution is added to a solution containing iodide ions is AgI.

The formula of the sulfite ion is SO32-.

The test and result for sulfite ions is to:

The test and result for nitrate ions is:

A cation is a positively charged ion.

A flame test is used to identify metal ions by the colour of the flame they produce when heated.

True. The Bunsen burner flame should be on a blue flame for flame tests as this is the hottest flame.

The flame colour produced by sodium ions is yellow.

The flame colour produced by copper ions is blue -green.

False. The flame colour produced by potassium ions is lilac.

The flame colour produced by calcium ions is orange-red.

True. The flame colour produced by lithium ions is red.

The nichrome wire is first dipped in hydrochloric acid to avoid contamination.

The flame colour produced by barium ions is apple-green.

The colour of the precipitate formed when sodium hydroxide is added to a solution containing copper(II) ions is blue.

False. Iron(III) ions form a brown precipitate in the presence of sodium hydroxide.

The colour of the precipitate formed by iron(II) ions in the presence of sodium hydroxide is green.

False. Ca2+ form a white precipitate in the presence of sodium hydroxide.

The test for ammonium ions is:

False. The green precipitate formed by Cr3+ ions will dissolve in excess sodium hydroxide solution to give a green solution.

A test using sodium hydroxide to distinguish between solutions containing Al3+ ions and Ca2+ ions is:

True. When ammonia is added to a solution containing Zn2+ ions, a white precipitate forms.

When ammonia solution is added to a solution containing aluminium ions, a white precipitate is formed.

False. When excess ammonia is added to a precipitate containing Cr3+ ions, the precipitate does not dissolve, it only dissolves in excess NaOH.

The test and result for hydrogen gas is a lit / burning splint makes a 'squeaky pop' sound.

The test and result for oxygen gas is a glowing splint relights.

The test and result for carbon dioxide gas is limewater turns cloudy / milky.

The test and result for chlorine gas is that damp litmus paper turns red and then bleaches white.

The test and result for ammonia gas is using damp red litmus paper which will turn blue.

False. Chlorine is a green pungent gas

The test and result for sulfur dioxide gas is to bubble the gas through acidified potassium manganate(VII) which changes from purple to colourless.