Seperation techniques

Question 1

when do we use filtration?

Answer 1

to separate an insoluble solid from a liquid eg sand and water

Question 2

what 2 pieces of equipment are needed for filtration

Answer 2

filter paper

filter funnel

Question 3

how do we carry out filtration?

Answer 3

1. filter paper is placed over filter funnel

2. solution is poured into filter paper and the liquid passes through but the solid stays in the filter paper

Question 4

when do we use crystallisation

Answer 4

to separate a soluble solid from a liquid eg sodium chloride and water

Question 5

what other technique could we use to separate a soluble solid from a liquid? how?

Answer 5

evaporation, heating the liquid over a Bunsen burner

Question 6

what are the issues with using evaporation?

Answer 6

some solids may thermally decompose at these temperatures

Question 7

what 4 equipments is needed for crystallisation

Answer 7

water bath
evaporating dish
tripod
heat source

Question 8

how do we carry out crystallisation

Answer 8

1. evaporating dish with solution is place in a water bath, this is placed above a tripod
2. heat it and stop at the point of crystallisation when small crystals form
3. after removing heat more crystals will start to form and the rest of the liquid is left to evaporate

Question 9

when is simple distillation used

Answer 9

to separate a liquid from a solution

Question 10

what 5 pieces of equipment are used in simple distillation

Answer 10

flask
bung
thermometer
condenser (made of main pipe and water jacket)
beaker

Question 11

how do we carry out simple distillation

Answer 11

1. place mixture in flask and cover with bung
2. thermometer is put through the bung to monitor the temperature
3. attached to the flask is the condenser
4. the solution is heated to a certain temperature and gas rises and condenses at water jacket
5. the liquid is collected in a beaker