Abdul Binah
Unit 2: Practical Scientific Procedures and
Techniques
Keeping up the standards
Cooling curve of steric acid and paraffin wax.
I am a newly appointed technical assistant at a large
chemical plant, Chemcalequip. As part of my induction
period and to progress in my role, I had to
demonstrate skills in a range of practical procedures and
techniques. Part of my role is to ensure equipment is
calibrated and equipment and chemicals are safety checked.
I needed to demonstrate my ability to use a calorimeter
and associated equipment to obtain data to determine,
analyse and evaluate the rate of cooling of certain substances.
Hypothesis-
I predicted that the results of the cooling curve would appear as a line of best fit with a gradient of -2.
The temperature of the steric acid would alter by 1.4 c° every 60 seconds; the temperature of paraffin
wax would alter by 2.4 c° every 60 seconds.
Aim-
The purpose of this practical is to undertake calorimetry to compare the cooling curve of paraffin wax
and steric acid in order to produce reproducible results on a cooling curve graph, analyse the difference
between the graphs and evaluate the method used to commence the experiment and potentially
suggest any improvements to get acceptable results if not previously obtained.
, Risk assessment-
•Wear safety goggles when carrying out this experiment.
•Make sure any beakers are on the centre of tables to avoid glass shattering when falling from elevated
surfaces.
• Be aware of boiling water spillage when transferring from kettle to beakers + boiling tubes and when
handling hot glassware.
• You must tie long hair back, put away lanyards and tuck in ties; you may also consider wearing
protective clothing such as handwear and a lab coat because of danger from boiling water and acidic
substance.
! Attention! Steric acid is being used and is a skin irritant. In any case the acid comes in contact with
your skin, you must wash it off immediately.
Apparatus/equipment-
• Liquid glass thermometer
• Digital thermometer/ ethanol-based thermometer (digital thermometer didn’t fit in test tube)
• Boiling tubes
• Boiling tube stand
• Stopwatch
• Beakers
• Steric acid
• Paraffin wax
• Ice
• Boiling water
• Kettle
• Graph paper
• Pencil
Unit 2: Practical Scientific Procedures and
Techniques
Keeping up the standards
Cooling curve of steric acid and paraffin wax.
I am a newly appointed technical assistant at a large
chemical plant, Chemcalequip. As part of my induction
period and to progress in my role, I had to
demonstrate skills in a range of practical procedures and
techniques. Part of my role is to ensure equipment is
calibrated and equipment and chemicals are safety checked.
I needed to demonstrate my ability to use a calorimeter
and associated equipment to obtain data to determine,
analyse and evaluate the rate of cooling of certain substances.
Hypothesis-
I predicted that the results of the cooling curve would appear as a line of best fit with a gradient of -2.
The temperature of the steric acid would alter by 1.4 c° every 60 seconds; the temperature of paraffin
wax would alter by 2.4 c° every 60 seconds.
Aim-
The purpose of this practical is to undertake calorimetry to compare the cooling curve of paraffin wax
and steric acid in order to produce reproducible results on a cooling curve graph, analyse the difference
between the graphs and evaluate the method used to commence the experiment and potentially
suggest any improvements to get acceptable results if not previously obtained.
, Risk assessment-
•Wear safety goggles when carrying out this experiment.
•Make sure any beakers are on the centre of tables to avoid glass shattering when falling from elevated
surfaces.
• Be aware of boiling water spillage when transferring from kettle to beakers + boiling tubes and when
handling hot glassware.
• You must tie long hair back, put away lanyards and tuck in ties; you may also consider wearing
protective clothing such as handwear and a lab coat because of danger from boiling water and acidic
substance.
! Attention! Steric acid is being used and is a skin irritant. In any case the acid comes in contact with
your skin, you must wash it off immediately.
Apparatus/equipment-
• Liquid glass thermometer
• Digital thermometer/ ethanol-based thermometer (digital thermometer didn’t fit in test tube)
• Boiling tubes
• Boiling tube stand
• Stopwatch
• Beakers
• Steric acid
• Paraffin wax
• Ice
• Boiling water
• Kettle
• Graph paper
• Pencil
