chemical tests Flashcards
1
Q
Test for aldehydes and ketones
A
- 2,4-DNP
- orange ppt —> +ve test
2
Q
Test for aldehydes
A
- Tollens reagent - silver nitrate and ammonia
- silver mirror if aldehyde present
3
Q
What does iodine and NaOH test for?
A
- iodoform!
- methyl ketones
- yellow ppt
4
Q
Test for amides
A
- alkaline hydrolysis - heat with NaOH
- produce ammonia gas if amide (litmus paper go blue)
5
Q
Test for esters
A
- alkaline hydrolysis - heat with NaOH
- produce sodium carboxylate salt
- add H2SO4 to produce carboxylic acid
6
Q
Test for alkenes
A
- add Br2
- decolourise
7
Q
Test for alcohols
A
- add H+/K2Cr2O7
- orange to green
8
Q
Test for halogenoalkanes
A
- add NaOH then add AgNO3
- white, cream and yellow ppt
9
Q
Lithium flame test
A
Red
10
Q
Sodium flame test
A
Yellow
11
Q
Potassium flame test
A
Lilac
12
Q
Rubidium flame test
A
Red
13
Q
Magnesium flame test
A
Colourless
14
Q
Calcium flame test
A
Brick red
15
Q
Strontium flame test
A
Crimson
16
Q
Barium flame test
A
Apple green
17
Q
Solubility of group 1 compounds
A
All soluble
18
Q
Solubility of group 2 compounds
A
- all nitrates are soluble
- all carbonates are insoluble
- hydroxides increase in solubility as you descend
- sulfates become less soluble as you descend
