... has the same number of bonds.

... has the same number of atoms, but different elements.

... has the same number and type of atoms, but a different arrangement.

... has the same arrangement of atoms, but different numbers.

C_nH_2n

C_nH_2n+1

C_nH_2n+2

C_nH_2n+3

C₂H₆

CH₆

C₂H₄

CH₄

C₅H₁₀

C₅H₁₂

C₃H₆

C₃H₈

Same general formula.

Differ by CH₂ in molecular formulae from neighbouring compounds.

Show gradual variation in physical properties.

Have similar chemical properties.

Crystallisation

Filtration

Simple distillation

Fractional distillation

Bitumen

Kerosene

Petrol

Fuel oil

Bitumen

Kerosene

Petrol

Fuel oil

Fuel oil is a larger molecule than petrol.

Fuel oil is more volatile than petrol.

Fuel oil has a lower boiling point than petrol.

Fuel oil is more viscous than petrol.

Water

Carbon

Carbon monoxide

Carbon dioxide

Binds to haemoglobin in the place of oxygen.

Causes slow suffocation.

Is highly flammable.

Is a heavy gas.

Are present in the atmosphere in large proportions.

Always react together.

React together in car engines due to the high temperatures.

Are both ionically bonded structures.

Colourless to brown.

Effervescence

Brown to colourless

Orange to red

$Br\ +C_2H_4\ \rightarrow\ C_2H_4Br$

$2Br_2\ +C_2H_4\ \rightarrow\ 2HBr\ +C_2H_2Br_2$

$Br_2\ +C_2H_4\ \rightarrow\ C_2H_4Br_2$

$2Br_2\ +C_2H_4\ \rightarrow\ C_2H_4Br_2\ +2HBr$