Qualitative Analysis + Reactions of metals Flashcards
Colours of metals (those in the reactivity series)
K & Na: Dull grey solid Ca - Pb: Silvery grey solid Cu: Reddish brown Hg: Silver liquid Ag: Shiny silver liquid Au: Shiny gold liquid Pt: Shiny silver solid
Reactivity of metals with water
K - Ca: React with cold water –> Alkali + hydrogen
Mg - Pb: React with steam –> Metal oxide + hydrogen
Cu onwards: No reaction
Reactivity of metals with oxygen
K - Hg: React with oxygen –> Metal oxide
Below Hg: No reaction
Colours of group I, II & III, and ammonium compounds
White solid
Colour of zinc oxide
Yellow when hot, white when cold
Reactivity of metals with dilute acids
K - Pb: React –> Salt + hydrogen
Colour of iron(II) oxide
Black
Colour of iron (III) oxide
Reddish brown
Colour of copper(II) oxide
Black
Colour of copper(I) oxide
Reddish brown
Colour of copper(II) carbonate
Green
Colour of copper(II) sulfate
Blue
Colour of copper(II) chloride solution
Bluish green
Colour of copper(II) hydroxide (insoluble)
Blue
Colour of zinc hydroxide (insoluble)
White
Colour of iron(II) hydroxide (insoluble)
Dirty green
Colour of iron(III) hydroxide (insoluble)
Reddish brown
Colour & state of carbon
Black solid
Colour & state of fluorine at rtp
Pale yellow gas
Colour & state of bromine at rtp
Reddish brown liquid
Colour of iodine (all states)
Black solid, yellow-brown liquid, violet vapour
Change in colour of potassium manganate(VII) KMnO4`
When reduced, turns from purple –> colourless
Change in colour of potassium dichromate(VI) K2Cr2O7`
When reduced, turns from orange –> green
Black oxides
Copper(II) oxide, Iron(II) oxide, Manganese(IV) oxide
Identification of aluminium ion
NaOH
White precipitate Al(OH)3 formed
Dissolves in excess NaOH
NH3
White precipitate Al(OH)3 formed
Insoluble in excess NH3
Identification of lead(II) ion
NaOH
White precipitate Pb(OH)2 formed
Dissolves in excess NaOH
NH3
White precipitate Pb(OH)2 formed
Insoluble in excess NH3
Identification of zinc ion
NaOH
White precipitate Zn(OH)2 formed
Dissolves in excess NaOH
NH3
White precipitate ZN(OH)2 formed
Dissolves in excess NH3
Identification of calcium ion
NaOH
White precipitate Ca(OH)2 formed
Insoluble in excess NaOH
NH3
No precipitate
Identification of copper(II) ion
NaOH
Blue precipitate Cu(OH)2 formed
Insoluble in excess NaOH
NH3
Blue precipitate Cu(OH)2 formed
Dissolves in excess NH3 to give dark blue solution
Identification of iron(II) ion
NaOH
Dirty green precipitate Fe(OH)2 formed
Insoluble in excess NaOH
NH3
Dirty green precipitate Fe(OH)2 formed
Insoluble in excess NH3
Identification of iron(III) ion
NaOH
Reddish brown precipitate Fe(OH)3 formed
Insoluble in excess NaOH
NH3
Reddish brown precipitate Fe(OH)3 formed
Insoluble in excess NH3
Identification of ammonium ion
NaOH
No precipitate
Pungent ammonia gas evolved on heating
NH3
No reaction
Identification of halide ions
Add dilute nitric acid + aqueous silver nitrate
Chlorine: White precipitate AgCl
Iodine: Yellow precipitate AgI
Identification of carbonate ion
Add dilute hydrochloric acid
Carbon dioxide gas produced
Identification of nitrate ion
Add aqueous sodium hydroxide + a small amount of aluminium powder + warm the mixture
Pungent ammonia gas produced
Identification of sulfate ion
Add dilute nitric acid + barium nitrate
White precipitate BaSO4 formed
Identification of hydrogen
Extinguishes lighted splint with a ‘pop’ sound
Identification of oxygen
Rekindles glowing splint
Identification of carbon dioxide
Forms a white precipitate with limewater Ca(OH)2
Precipitate: CaCO3
Identification of ammonia
Turns damp red litmus paper blue
Pungent smell
Identification of chlorine
Turns damp blue litmus paper red
Greenish yellow gas, choking smell
Identification of nitrogen dioxide gas
Reddish brown in colour, pungent
Identification of sulfur dioxide gas
Smell of burnt matches