Chemical + Ion Tests Flashcards
1
Q
What is the test for distinguishing between alkenes and alkanes?
A
- Bromine water
- Tests for C=C in alkenes
2
Q
What is the 1st test for distinguishing between aldehydes and ketones?
A
- Acidified potassium Manganate (KMnO4)
- Oxsidises aldehydes forming carboxylic acid
- Soution colour change from purple to colourless
- Ketones dont react
- Solution has no colour change
3
Q
What is the 2nd test for distinguishing between aldehydes and ketones?
A
- Tollens reagent
- Aldehydes will be oxsidised to carboxylic acids
- Forming a silver mirror
- Ketones wont react hence no silver mirror
4
Q
What is the 3rd test for distinguishing between aldehydes and ketones?
A
- Fehlings Test
- Aldehydes will be oxsidised to carboxylic acids
- Turning the solution from blue to brick red
- Ketones cant be oxsidised and will not have any colour change
5
Q
What is the test to detect a methyl ketone or secondary alcohol?
A
- Iodoform test
- These ketones will react within iodine in the presence of a base
- Forming a Yellow precipitate
6
Q
What is the test to detect carbonyl functional groups?
A
- Bradys reagent test (2,4-DNP)
- Aldehyde or ketone will react with 2,4-DNP
- Forming yellow or orange precipitate which can filtered and washed
7
Q
What are the steps for testing for carbonate ions?
A
8
Q
What is the test for sulfate ions?
A
9
Q
What is the test for ammonium ions?
A
10
Q
What is the test for halide ions?
A
- Add to silver nitrate
- Each will form different precipitates
- Chloride = White
- Bromide = Cream
- Iodide = yellow
11
Q
How do you test for an aldenhyde or a primary / secondary alcohol
A
- Add acidified potassium dichromate
- This will oxsidise (colour change orange to green)
- Aldeydes -> ketones
- Primary alcohol -> secondary
- Secondary alchol -> tertiary
