test for ions usimng NaOH Flashcards
(16 cards)
what is the other method of testing for postive ions and what is it for?
using sodium hydroxide and testing postoive ions in a soloution formed
what else can be used and why?
all types of hydroxides because they are insolouble and can precipitate out of a soloution
breifley expalin the process of testing postive ions of soloutions
you add hydroxide (most time sodium) and add a few drops to the soloution of mystery coimpound
-then an insolouble hydroxixe is formed
-this insoluble coloured hydroxide allows us to identify which positve ions are present
what is the acronym for the posirtve ions table ?
a -aluminium 3+
zebra-zinc 2+
said -silverβ> Ag+
lets- leadβ> pb2+
chant-copperβ>cu2+
calim 2+
iron2+
iron 3+
what is the colour of the precipitste of aluminium ion
white
-dissolves in excess sodium bhdroxie
what is the colour of precipitate of zinc ion
white
-dissolves in excess sodium byrdroixse
what is the colour of the precipitate of silver and what is formed?
-brown(silver oxide)
what is the colour of the precipitate formed from the ion lead ?
white
what is the colour of the precipitate formed from the ion copper?
blue
what is the colour of the precipitate formed from the ion iron 2+
green
what is the colour of the precipitate formed from the ion iron 3+?
brown-red
what state must the precipitate formed be in?
a solid state
what is the ionic equation for the aluminium 3+ ion AND STATE THE STATE SYMBOLS?
al3+ + 3OH- β> al(OH)3
(aq) (aq) β> (s)
al(OH)3 + OH- β> Al(OH)4 , -^
(s) (aq) (aq)
what is the ionic equatiion for the zinc 2+ ion?
Zn2+ + 2OH- β> Zn(OH)2
(aq) (aq) (S)
Zn(OH)2 + OH- β> Zn(OH)3 , -
(s) (aq) (aq)
what is the ionic equiation for silver?
2Ag+ + OH- β> AgO2 + H2O
What would the ionic equations be for the rest of the ions for exampple copper?
Cu2+ + 2OH- β> Cu(OH)2
