AS2.11 Organic Synthesis

Question 1

Büchner funnel

Answer 1

When making a solid organic product

Leave sample on filter paper under reduced pressure allows sample to air dry

Rinse solid on filter paper to remove solvent and any remaining soluble impurities

Question 2

Recrystallisation

Answer 2

Dissolve the sample in minimum amount of hot solvent

Cool in ice bath to recrystallise

Filter under reduced pressure and wash with cold water

Leave to dry

Question 3

Using capillary tube

Answer 3

Capillary tube with one sealed end - open end tapped on solid sample

Tube then inverted and tapped gently to encourage sample to drop down inside tube to sealed end

Question 4

How to check purity

Answer 4

Compare melting points

Gives a narrow range which is compared to data book value to assess purity or identify compound

Narrower range = purer sample