quantitative analysis Flashcards
green coloured compounds
copper (II) carbonate
iron (II) salts
blue coloured compounds
copper (II) salts
brown coloured compounds
copper metal, iron (III) compounds
black coloured compounds
copper (II) oxide, iron (II) oxide, carbon, iodine crystals??
yellow coloured compounds
lead (II) oxide, lead (II) iodide, silver bromide, silver iodide
cations in cation tests
zinc, aluminium, calcium, copper (II), iron (II), iron (III), ammonium, sodium, potassium
solubility of zinc ions in reagents
white ppt (Zn(OH)2); soluble in excess
white ppt (Zn(OH)2); soluble in excess
solubility of aluminium ions in reagents
white ppt Al(OH)3; soluble in excess
white ppt Al(OH)3; insoluble in excess
solubility of calcium ions in reagents
white ppt Ca(OH)2; soluble in excess
no ppt formed
solubility of Cu2+ ions in reagents
blue ppt Cu(OH)2; insoluble in excess
blue ppt Cu(OH)2; soluble in excess
solubility of Fe2+ ions in reagents
green ppt Fe(OH)2; insoluble in excess
green ppt Fe(OH)2; insoluble in excess
solubility of Fe3+ ions in reagents
red brown ppt; insoluble in excess
red brown ppt; insoluble in excess
solubility of nh4+ ions in reagents
no ppt; ammonia given off upon heating
no ppt
why dont calcium ions form a precipitate in aqueous ammonia
aqueous ammonia has a low concentration of OH- ions so hard for products to form, and Ca(OH)2 is partially soluble in water, meaning any product formed is likely dissolved
why are most precipitates insoluble in excess
most metal hydroxides are basic and are insoluble in bases because they react with acids. exceptions are zinc and aluminium because they are amphoteric