separating mixtures

Question 1

what does distillation separate

Answer 1

a soluble solid from a solution
used when solvent is required

Question 2

distillation method

Answer 2

heat solution so the water boils and rises through the flask into the condenser. solid remains in the flask

Question 3

what does fractional distillation separate

Answer 3

2 or more miscible liquids

Question 4

fractional distillation method

Answer 4

mixture is placed in a flask and heated
mixture boils. vapours pass into a fractionating column, but there is a higher proportion of the substance with the lower bpt.
in the fractionating column they condense and reboil many times, each with a higher proportion of the more volatile liquid.
as a result of this, the vapour of the more volatile liquid emerges from the top of the column first, in a pure sate, and passes through the condenser.
when all this liquid has been distilled over, it is followed by the substance with the higher bpt.

Question 5

what does a separating funnel separate

Answer 5

immiscible liquids

Question 6

what does chromatography separate

Answer 6

several solids that are all soluble in the same solvent

Question 7

chromatography method

Answer 7

take a piece of chromatography paper
draw a pencil line on the paper about 2cm from the bottom
place the dye on the pencil line
label each spot with a pencil
place 1cm depth of water into a beaker
place the chromatography paper into the beaker so that the paper is in the water, but below the level of the dye
leave the paper in the water until the water is near the top of the paper and then take the paper out to dry

Question 8

Rf value =

Answer 8

distance moved by pigment / distance from origin to solvent front

Question 9

hat is recrystallisation

Answer 9

a method of purifying a solid and removing both insoluble and soluble impurities