Paper Chromatography

Question 1

Chromatography

Answer 1

A method of separating mixtures of soluble substances

Question 2

Mixture

Answer 2

Contains 2 or more substances not chemically combined

Question 3

Solvent

Answer 3

a substance that dissolves a solute

Question 4

Stationary phase

Answer 4

Is the paper in paper chromatography

Question 5

Mobile phase

Answer 5

Is the solvent in paper chromatography

Question 6

Chromatogram

Answer 6

Shows the results of separating the components of a mixture by chromatography

Question 7

Pure substance

Answer 7

A substance that’s contains a single elements or compound not mixed with any other substance

Question 8

Impure substance

Answer 8

Is made of more than one thing and produces two or more spots on a chromatogram

Question 9

Rf value

Answer 9

A way of measuring how far a spot has travelled on a chromatogram compared to the distance the solvent has travelled

Question 10

Solvent front

Answer 10

The furthest point the solvent travels in paper chromatography

Question 11

Soluble

Answer 11

a substance that is dissolved in a solvent

Question 12

Pencil line

Answer 12

Doesn’t dissolve in the solvent so can be used as a baseline to make measurements in paper chromatography

Question 13

Which piece of equipment is used to measure time and are the units? [2]

Answer 13

Stopwatch in seconds

Question 14

Which piece of equipment is used to measure temperature and what are the units? [2]

Answer 14

Thermometer in degrees celsius

Question 15

Which piece of equipment is used to measure mass and what are the units? [2]

Answer 15

Mass balance in grams

Question 16

Which 3 pieces of equipment are used to measure volume of a liquid and what are the units? [4]

Answer 16

measuring cylinder, volumetric pipette and burette in cm³

Question 17

how to measure volume (gas) and unit

Answer 17

gas syringe in cm³

Question 18

what process is used to separate two or more solids that are soluble [1]

Answer 18

paper chromatography

Question 19

how do you calculate Rf value in paper chromatography? [1]

Answer 19

Distance moved by solute divided by distance moved by solvent

distance of solute/distance of solvent

Question 20

Describe 3 ways that the purity of a substance can be assessed [3]

Answer 20

Melting point, boiling point, chromatography

Question 21

Describe how melting point/ boiling point can be used to access purity [2]

Answer 21

A pure substance will have a sharp melting point / boiling point.
An impure substance will melt over a temperature change

Question 22

Describe how chromatography can be used to assess purity [1]

Answer 22

A pure substance will produce only one well defined spot on a chromatogram

Question 23

Describe two examples of where purity of substances is important [2]

Answer 23

manufacture of compounds used in drugs and food additives

Question 24

solution

Answer 24

a liquid mixture

Question 25

volatility

Answer 25

how easily a substance evaporates / changes from a liquid to a gas

Question 26

solubility

Answer 26

how easily a substance dissolves

Question 27

what is filtration used for? [1]

Answer 27

to separate a insoluble solid from a liquid

Question 28

What is filtrate in filtration? [1]

Answer 28

the liquid or solution that has passed through the filter

Question 29

What is crystallisation? [1]

Answer 29

the liquid that contains a dissolved salt is evaporated to leave the salt behind

Question 30

What is distillation used for? [1]

Answer 30

to separate a solvent from a solution

Question 31

What is the difference between immiscrible and miscible liquids? [2]

Answer 31

immiscibele liquids don’t mix, miscrible liquids do mix

Question 32

how can immiscible liquids be separated? [1]

Answer 32

by using a separating funnel