Assessed practical 6 (AS)
Aim: To determine whether ethanol has been oxidised to ethanal or oxidised to ethanoic acid.
Method and observations
- 2 cm3 of sulphuric acid was added to a pear shaped flask containing 6 cm3 of water. Whilst the volume for the water was measured using a measuring cylinder (of 10 cm3 capacity), the volume of the sulphuric acid was measured using a graduated dropping pipette. Both readings were sighted and taken from the bottom of the meniscus.
Observation: As the sulphuric acid was added to the water, there was significant emission of heat implying that an exothermic reaction took place.
- The apparatus were then set up as shown below:
All joints were greased with petroleum jelly in order to ensure that there would be no loss of the vapour produced from the system. Anti-bumping granules were added to the pear shaped flask in order to prevent the sudden formation of large gas bubbles that lead to ‘bumping’ or large succussion.