Inorganic Chemistry - Chemical Tests

use a lit splint, if gas is present the gas will pop

use a glowing splint, if gas is present the splint will relight

bubble the gas through limewater, if gas is present limewater turns cloudy

use red litmus paper, if gas is present litmus paper will turn blue

use damp litmus paper, if gas is present litmus paper turns white (bleached)

• a platinum or nichrome wire (inert, high melting point) is dipped into concentrated hydrochloric acid to remove impurities • the wire is dipped into the salt being tested so some salt sticks to the end • the wire and salt are held in a non-luminous (roaring) bunsen burner flame • the colour is observed

red

yellow

lilac

orange-red

blue-green

• add sodium hydroxide and warm • if ammonium ions are present, ammonia gas will form • this will turn damp red litmus paper blue

• add sodium hydroxide • a blue precipitate of copper hydroxide will form

• add sodium hydroxide • a green precipitate of iron(II) hydroxide will form

• add sodium hydroxide • a brown precipitate of iron(III) hydroxide will form

• add hydrochloric acid • if carbonate ions are present, fizzing will occur • test the gas for carbon dioxide using limewater

• add nitric acid to remove impurities • add silver nitrate solution • if chloride is present then a white precipitate of silver chloride is formed

• add nitric acid to remove impurities • add silver nitrate solution • if bromide is present then a cream precipitate of silver bromide is formed

• add nitric acid to remove impurities • add silver nitrate solution • if iodide is present then a yellow precipitate of silver iodide is formed

• add hydrochloric acid to remove impurities • add barium chloride • if sulfate ions are present, a white precipitate of barium sulfate will form

• add anhydrous copper (II) sulfate to a sample • if water is present the anhydrous copper (II) sulfate will change from white to blue

if the sample is pure water it will boil at 100C