Paper 3: Required practical 6 - Organic tests

Question 1

How do you test for an alcohol?

Answer 1

• Add 1cm^3 opf alcohol to a test tube, add a small piece of sodium
• White precipitate and effervescence

Question 2

How do you distinguish between different alcohol types?

Answer 2

• Heat under reflux with acidified potassium dichromate
• Primary and secondary alcohols wil be oxidised - orange to gree

Question 3

How do you test for an aldehyde?

Answer 3

• Add Fehling’s solution
• Brick red ppt will form

Question 4

How do you test for an alkene?

Answer 4

• Add bromine water
• Will decolourise from orange

Question 5

How do you test for a carboxylic acid?

Answer 5

• Add Na2CO3 to the sample
• CO2 will be given off

Question 6

How do you test for a haloalknae?

Answer 6

• Add 5 drops of haloalkane to abut 1 cm^3 of NaOH solution in a test tube
• Warm the contents of the test tube at 60°C for a few minutes
• Add 2cm^3 of dilute nitric acid and 1cm^3 of silver nitrate solution
• If a haloalkane is present, a ppt should form
• White - chloride Cream - bromide Yellow - iodide