[2]
Comparing hydrocarbons
Aims
The purpose of this activity is to compare how three liquid hydrocarbons – cyclohexane (an alkane),
cyclohexene (an alkene) and methylbenzene (an arene) – behave with a series of chemical reagents.
Safety
Concentrated sulfuric acid must not be available in the laboratory at the same time as solid
potassium (VII) manganate.
Solid potassium (VII) manganate is a powerful oxidising agent. It causes staining of skin and clothes.
Wear chemical-resistant gloves.
Cyclohexene, cyclohexane and methylbenzene are harmful and highly flammable, keep bottles
stoppered when not in use and well away from naked flames. Work in a well ventilated laboratory
and do not breathe the vapours. Avoid skin contact and wear chemical-resistant gloves.
Bromine is corrosive and gives off a toxic vapour. Work in a fume cupboard, avoid breathing the
fumes and wear goggles and chemical-resistant gloves. Handle the solution with care – measure out
in a fume cupboard using a marked pipette.
Concentrated ammonia solution is corrosive and releases toxic ammonia gas. The concentrated
solution must be used in a fume cupboard.
Chemicals and equipment
Thermometer Cyclohexane
100cm3 beaker Cyclohexene
250cm3 conical flask Methyl benzene
10cm3 measuring cylinder Methyl benzoate
Test tubes, bungs and rack Concentrated nitric acid
Boiling tubes Potassium manganate solution 0.02M
Teat pipettes Potassium manganate crystals
Glass rod Solid sodium carbonate
Crushed ice Sodium disulfite(IV) solution 1M
Concentrated ammonia solution Sulfuric acid 1M
Bromine water 0.02 Concetrate sulfuric acid
Bromine in cyclohexane solution 1-5%
Introduction
Arenes have characteristic properties that are very different to those shown by alkanes and alkenes. In this
activity you will compare the reactions cyclohexane, cyclohexene and methylbenzene. (Benzene cannot be
used due to its carcinogenic properties).
Original: Salters Practical CD4.1
Comparing hydrocarbons
Aims
The purpose of this activity is to compare how three liquid hydrocarbons – cyclohexane (an alkane),
cyclohexene (an alkene) and methylbenzene (an arene) – behave with a series of chemical reagents.
Safety
Concentrated sulfuric acid must not be available in the laboratory at the same time as solid
potassium (VII) manganate.
Solid potassium (VII) manganate is a powerful oxidising agent. It causes staining of skin and clothes.
Wear chemical-resistant gloves.
Cyclohexene, cyclohexane and methylbenzene are harmful and highly flammable, keep bottles
stoppered when not in use and well away from naked flames. Work in a well ventilated laboratory
and do not breathe the vapours. Avoid skin contact and wear chemical-resistant gloves.
Bromine is corrosive and gives off a toxic vapour. Work in a fume cupboard, avoid breathing the
fumes and wear goggles and chemical-resistant gloves. Handle the solution with care – measure out
in a fume cupboard using a marked pipette.
Concentrated ammonia solution is corrosive and releases toxic ammonia gas. The concentrated
solution must be used in a fume cupboard.
Chemicals and equipment
Thermometer Cyclohexane
100cm3 beaker Cyclohexene
250cm3 conical flask Methyl benzene
10cm3 measuring cylinder Methyl benzoate
Test tubes, bungs and rack Concentrated nitric acid
Boiling tubes Potassium manganate solution 0.02M
Teat pipettes Potassium manganate crystals
Glass rod Solid sodium carbonate
Crushed ice Sodium disulfite(IV) solution 1M
Concentrated ammonia solution Sulfuric acid 1M
Bromine water 0.02 Concetrate sulfuric acid
Bromine in cyclohexane solution 1-5%
Introduction
Arenes have characteristic properties that are very different to those shown by alkanes and alkenes. In this
activity you will compare the reactions cyclohexane, cyclohexene and methylbenzene. (Benzene cannot be
used due to its carcinogenic properties).
Original: Salters Practical CD4.1
