Tests Flashcards
Oxygen gas
Relights a glowing splint
Hydrogen gas
Mix with air
Ignite
Burns with a squeaky pop
Carbon dioxide gas
Bubble through limewater (acid and carbonate)
Turns limewater milky
Chlorine gas
Damp litmus paper turns white
Moist starch-iodide paper turns blue
Ammonia gas
Heat up with sodium hydroxide in a boiling tube
Damp red litmus paper turns blue
Damp universal indicator paper turns purple
Carbonate ions using dilute acid
To the solid or an aqueous solution of it
Add dilute hydrochloric/ nitric acid
Bubbles of gas are formed
The gas formed turns limewater milky
Surface ions by precipitation with barium chloride solution
To an aqueous solution of the solid under test
Add dilute hydrochloric acid followed by a few drops of barium chloride
White precipitate of barium sulfate formed
Halide ions by precipitation with silver nitrate solution (anion)
Aqueous solution of the solid under test
add some dilute nitric followed by a few drops of silver nitrate solution
Chloride ion (precipitate test)
White precipitate
Silver chloride
Bromide ion (precipitate test)
Cream precipitate
Sliver bromide
Iodide ion (precipitate test)
Yellow precipitate
Silver iodide
Metal cations
Metal cations
Most metal cations are insoluble, can be precipitated by adding sodium hydroxide
Copper (ii) (precipitate)
Blue precipitate
Iron (ii) (precipitate)
Green precipitate
Iron (iii) (precipitate)
Brown precipitate
Flame test
Metal cations
Platinum or inch nichrome wire dipped into hydrochloric acid (put into Bunsen burner first until has no colour) repeat
then into the solid sample
Lithium (flame test)
Red
Potassium (flame test)
Lilac
Calcium (flame test)
Brick red
Sodium (flame test)
Yellow/ orange
Ammonium ion
Add aqueous sodium hydroxide to the solid
Warm the mixture
Ammonium ions presents -> pungent smelling gas produced
Damp red litmus paper goes blue
