Unit 6A
P1. Carry out a literature search and review into a chosen scientific area.
P2. Produce an appropriate project proposal for an investigative project proposal, to
include hypothesis.
My project proposal is based on the preparation of phenyl benzoate in the laboratory.
Aim: To safely prepare phenyl benzoate in the laboratory.
Hypothesis: I predict that by reacting phenol with benzoyl chloride and excess sodium
hydroxide solution, benzoylation will occur to give phenyl benzoate.
Background information: Phenyl benzoate, C13H10O2, is a substance which appears as a
white crystalline powder at room temperature, with a melting point between 68 to 70 degrees
Celsius and boiling point of 298 to 299 degrees Celsius. It is a phenyl ester of benzoic acid and
for safety, all phenyl benzoate preparation should take place in a fume cupboard whilst wearing
safety goggles and gloves.
Phenol + Benzoyl Chloride (NaOH)→ Phenyl Benzoate + Hydrochloric acid
C6H5OH + C6H5COCl → C13H10O2 + HCl
Through thorough research, I decided to use this specific method with the aim to safely prepare
phenyl benzoate in the laboratory.
Method:
Dissolve 2.0 g of phenol in 30 cm3 of 2.0 M sodium hydroxide solution in a 250 cm3 conical
flask.
Add 4.0 cm3 of benzoyl chloride, stopper the flask securely and shake vigorously for 15
minutes.
At the end of this time, a solid product should be obtained which can be filtered off with suctional
pump, breaking up any lumps on the filter paper with a spatula.
Wash thoroughly with water and drain.
Re-crystallise the crude ester from methylated spirits using a quantity of hot solvent
approximately 1.5 times the minimum required for complete solution. This is to ensure that the
phenol benzoate does not separate until the temperature of the solution has fallen below the
melting point of the ester.
Phenyl benzoate separates as colourless crystals. (If the solution is not clearly, filter the hot
solution, but you must consult with the teacher in advance.)
Equipment: 2.0 grams of phenol, 30cm3 of 2.0M of sodium hydroxide solution, 4.0cm3 of
benzoyl chloride, methylated spirit (ethanol), 250cm3 conical flask, suctional pump, filter paper,
spatula, deionised water, sink and workstation.
P1. Carry out a literature search and review into a chosen scientific area.
P2. Produce an appropriate project proposal for an investigative project proposal, to
include hypothesis.
My project proposal is based on the preparation of phenyl benzoate in the laboratory.
Aim: To safely prepare phenyl benzoate in the laboratory.
Hypothesis: I predict that by reacting phenol with benzoyl chloride and excess sodium
hydroxide solution, benzoylation will occur to give phenyl benzoate.
Background information: Phenyl benzoate, C13H10O2, is a substance which appears as a
white crystalline powder at room temperature, with a melting point between 68 to 70 degrees
Celsius and boiling point of 298 to 299 degrees Celsius. It is a phenyl ester of benzoic acid and
for safety, all phenyl benzoate preparation should take place in a fume cupboard whilst wearing
safety goggles and gloves.
Phenol + Benzoyl Chloride (NaOH)→ Phenyl Benzoate + Hydrochloric acid
C6H5OH + C6H5COCl → C13H10O2 + HCl
Through thorough research, I decided to use this specific method with the aim to safely prepare
phenyl benzoate in the laboratory.
Method:
Dissolve 2.0 g of phenol in 30 cm3 of 2.0 M sodium hydroxide solution in a 250 cm3 conical
flask.
Add 4.0 cm3 of benzoyl chloride, stopper the flask securely and shake vigorously for 15
minutes.
At the end of this time, a solid product should be obtained which can be filtered off with suctional
pump, breaking up any lumps on the filter paper with a spatula.
Wash thoroughly with water and drain.
Re-crystallise the crude ester from methylated spirits using a quantity of hot solvent
approximately 1.5 times the minimum required for complete solution. This is to ensure that the
phenol benzoate does not separate until the temperature of the solution has fallen below the
melting point of the ester.
Phenyl benzoate separates as colourless crystals. (If the solution is not clearly, filter the hot
solution, but you must consult with the teacher in advance.)
Equipment: 2.0 grams of phenol, 30cm3 of 2.0M of sodium hydroxide solution, 4.0cm3 of
benzoyl chloride, methylated spirit (ethanol), 250cm3 conical flask, suctional pump, filter paper,
spatula, deionised water, sink and workstation.
