C2.1

Question 1

What is the relative atomic mass (R.A.M or Ar)

Answer 1

The mean mass of an atom of an element compared to 1/12 the mass of a carbon 12 atom

Question 2

What is the relative formula mass (R.F.M or Mr)

Answer 2

The mean mass of a unit of a substance compared to 1/12 the mass of a carbon 12 atom

Question 3

What is the empirical formula

Answer 3

An empirical formula shows the simplest whole number ratio of the atoms of each element in a compound

Question 4

What is a pure substance in science

Answer 4

A substance that contains just one element or compound

Question 5

What is a solute

Answer 5

A solid that you are trying to dissolve

Question 6

Solvent

Answer 6

The liquid used to dissolve the solid

Question 7

Solution

Answer 7

The dissolved solute and solvent together

Question 8

What does soluble mean

Answer 8

A dissolvable solid

Question 9

What does insoluble mean

Answer 9

A solid that doesn’t dissolve

Question 10

What is simple distillation

Answer 10

It separates a solvent from a solution. It relies on the solvent having a much lower boiling point than the solute. When the solution is heated, the solvent boils but the solute does not. The solvent escapes from the solution in its gas state by a condenser. It is then cooled and condensed back to its liquid state by a condenser.

Question 11

What is fractional distillation

Answer 11

Fractional distillation separates two or more substances from a mixture in the liquid state. It relies on each substance having a different boiling point and uses a special piece of equipment called a fractionating column.

Question 12

What does a labelled diagram of simple distillation of impure water contain

Answer 12

Thermometer
Hot water vapour
Impure water boiling 
Heat
Vapour condenses to liquid in the condenser 
Test tube
Cooling water out
Purified water
Cooling water in

Question 13

What apparatus does fractional distillation contain

Answer 13

Everything in simple distillation but it has a fractionating column as well.

Question 14

What is the mobile phase in paper chromatography

Answer 14

The substance that moves

Question 15

What is the stationary phase in paper chromatography

Answer 15

The paper

Question 16

What does the bonding of the stationary and mobile phase do

Answer 16

It affects how high or low the ink/subject moves

Question 17

What is usually in thin layer chromatography

Answer 17

Usually in a tank
Not water but a solvent
Has a lid
Has a TLC plate
Has a line and an x sample

Question 18

What is the stationary phase in Thin-layer chromatography

Answer 18

A plate of glass or plastic but it has a thin layer of alumina or silica powder spread over it

Question 19

How do you calculate the retention factor (Rf) in chromatography

Answer 19

Distance travelled by substance
————————————————
Distance travelled by solvent

Question 20

What do Rf values vary from

Answer 20

They vary from 0 - 1 and have no units. They are also in 2 decimal places

Question 21

What is the mobile phase in gas chromatography

Answer 21

An unreactive carrier gas such as nitrogen which does not react with the sample

Question 22

How would you separate salt in seawater (6 marks)

Answer 22

1. Bunsen burner would heat up the seawater at a blue flame
2. The water would evaporate up from the round bottom flask when it reaches 100 degrees Celsius.
3. The evaporated water would go up the evaporating tube and into the condenser
4. The evaporated gas would then go through the condenser where cooling water is flowing through around it and the gas will condense.
5. The pure water will drip down onto the beaker and the salt will be left over
6. The distillate is in the beaker and the salt is in the round bottomed flask and you would turn off the Bunsen burner.