Distillation of a product from a reaction - part 2 Flashcards
1
Q
How is distillation done after reflux>
A
- allow equipment to cool and rearrange for distillation
- condesner removed
- still head inserted intpo flask
- thermomenter place in side
- water-cooled condenser attached from side
2
Q
Why do joints need to be secure
A
volatile chemical do not escape
3
Q
What is also needed in distillation
A
- anti-bumping granules
- can cause liquid to splash into condenser, casuing impure prodicts, or blow the apparatus apart
4
Q
Why does water go in at the botom?
A
more efficient cooling and prevents back flow of water
5
Q
What is solvent extraction?
A
- shaking organic liquid with an aqueous solution in a seperating funnel
- the impurities are more soluble in the aquoeus solution and move into it
- the organic liquid and aqueous solution are immiscible and can be seperated
6
Q
What is the aqueous solution in solvent extraction usually? why is it used
A
sodium hydrogen carbonate solution to remove acidic impurities
7
Q
How is pressure released when shaking?
A
- invert and open tap
8
Q
How are the liquid seperated?
A
- allow seperating funnel to stand until the laters settle and seperate
- remove the stopper and open tap, to run off the bottom layer into a beaker
- when the bottom layer is nearly all drained, close tap partially to slow down flow and avoid the top layer leaving
- discard aqueous layer
- repeat with another portion
- more effective to carry out twice with smaller portions
9
Q
How do you detemine which layer is organic liquid?
A
- add more water, see which one increases in size
- or more dense liquid
