Testing for Cations Flashcards
1
Q
Testing Cations Flame Test
A
- sterilise platinum wire loop by dipping in dilute hydrochloric acid
- hold over blue flame until it burns colourlessly
- dip into desired testing sample
- pass over flame
- observe colour of flame and identify metal ion
2
Q
Lithium Ions
A
crimson flame test
3
Q
Sodium Ion
A
yellow flame test
4
Q
Potassium Ion
A
lilac flame test
5
Q
Calcium Ion
A
orange-red flame test
6
Q
Copper ion
A
green flame test
7
Q
Cons of Flame Test
A
- colour can be difficult to distinguish
- especially if there is only a low concentration of the metal compound
- mixture of metal ions can mask the colour of the flame
8
Q
Pros of Manual method
A
- basic/simple
- cheap
9
Q
Metal Hydroxide Precipitates
A
- add sodium hydroxide solution to metal ion nitrate solution
- observe precipitate
10
Q
Copper(II) ions Precipitate
A
- blue precipitate
- copper (II) hydroxide (and sodium nitrate) produced
11
Q
Iron(II) ions Precipitate
A
- green precipitate
- iron (II) hydroxide (and sodium nitrate) produced
12
Q
Iron (III) ions Precipitate
A
- brown precipitate
- iron (III) hydroxide (and sodium nitrate) produced
13
Q
Calcium Ions Precipiatate
A
white precipitate
14
Q
Aluminium Ions Precipitate
A
white precipitate
15
Q
Magnesium Ions Precipitate
A
white precipitate
