C4 testing Flashcards
what chemical test is used for cations
sodium hydroxide
what other test can be used for cations
flame test
in the sodium hydroxide test, what colour precipitate copper make?
blue
in the sodium hydroxide test, what precipitate does iron(ii) make?
green
in the sodium hydroxide test, what precipitate does iron(iii) make?
orange-brown precipitate
in the sodium hydroxide test, what precipitate does zinc make?
white precipitate (not colourless)
in the sodium hydroxide test, what precipitate does calcium make?
white precipitate (not colourless)
in the flame test, what colour does lithium turn?
crimson
in the flame test, what colour does calcium turn?
orange-red
in the flame test, what colour does sodium turn?
yellow
in the flame test, what colour does copper turn?
green
in the flame test, what colour does potassium turn?
lilac
what is the test for carbonates?
add a small amount of dilute HCL and collect any gas produced and bubble it with limewater to check if carbon dioxide gas has been produced because, carbonate+acid—> salt+water+carbon dioxide.
what’s is the test for halides?
add dilute nitric acid followed by silver nitrate solution
what precipitate does chloride form in the halide test
white precipitate
what precipitate does bromide form in the halide test
cream precipitate
what precipitate does iodide form in the halide test
yellow precipitate
what is the test for sulfates
add dilute HCL followed by barium chloride
what happens if sulfate ions are present in the sulfate test
a white precipitate will form
how to tell zinc and calcium apart
add excess sodium hydroxide as only zinc ions will dissolve in excess solution whereas calcium would not
