Unit 2: Practical scientific procedures and techniques
Learning Aim B: Undertake calorimetry to study cooling curves
Assignment title: Keeping up the standards
Aims:
Obtain data using different equipment to construct cooling curves
Use cooling curves to determine the cooling rate of different substances
Abstract:
I have been appointed as a technical assistant at a chemical plant called
chemcalequip. In order to progress my role, I need to demonstrate skills in a
range of practical procedures. A part of my role is to make sure that equipment
is correctly calibrated and that the equipment and chemicals are safety
checked. I also need to demonstrate my ability to use a calorimeter and
associated equipment to obtain data to determine, analyse, and evaluate the
rate of cooling of substances. I am going to present evidence of my practical
skills analysis and evaluation in a report.
Calorimetry is the scientific investigation using a calorimeter to measure
changes in state, phase, and chemical reactions in terms of heat energy
transferred.
In this assignment I used a cooling curve to determine the rate of cooling of
substances. I obtained data using the equipment provided to construct cooling
curves, analysed the rate of cooling of substances from recorded data, and
evaluated the accuracy of the practical. Moreover, I also calibrated the
thermometers, alcohol, mercury, and digital thermometers. Calibrating
thermometers updates the indications and therefore allowed me to maintain
accurate, reliable, and consistent results when taking temperatures.
Risk assessments:
, Broken glassware safety assessment: Glass is medium hazard (can cause cuts)
Typical measures to reduce risk: Wear safety goggles and gloves. Keep
glassware at the centre of the workspace/table.
Emergency action: if you notice a glass shard has penetrated the skin, use
tweezers cleaned with rubbing alcohol to remove the glass.
Hot water: Hot water is a low hazard (Can cause skin irritation)
Typical measures to reduce risk: Wear safety gloves and goggles. Stir mixtures
to allow for an even distribution of heat.
Emergency action: if the hot water comes in contact with the skin, wash with
cold water to prevent burns.
Paraffin wax safety assessment: Wax is low hazard (can cause irritation)
Typical measures to reduce risk: Ensure to use the smallest amount of the
substance. Make sure to wear eye protection. Make sure the room is well
ventilated.
Emergency action: if it comes in contact with the eyes, wash the eyes with
water repeatedly.
Stearic acid safety assessment: The acid is an irritant
Typical measures to reduce risk: Ensure the room is well ventilated. You also
need to place the acid in the middle of the table to decrease the chance of
spillages. Wear eye protection (safety goggles)
Emergency action: if the acid comes in contact with the skin remove the
contaminated clothing and then wash the skin with water.
Calibration of thermometers:
Thermometers measure temperature and not heat. Heat is a form of energy
measured in joules whereas temperature is the measure of how hot something
is in degrees Celsius (°C).
Equation relating energy, temperature and heat:
Q=mc∆T
Learning Aim B: Undertake calorimetry to study cooling curves
Assignment title: Keeping up the standards
Aims:
Obtain data using different equipment to construct cooling curves
Use cooling curves to determine the cooling rate of different substances
Abstract:
I have been appointed as a technical assistant at a chemical plant called
chemcalequip. In order to progress my role, I need to demonstrate skills in a
range of practical procedures. A part of my role is to make sure that equipment
is correctly calibrated and that the equipment and chemicals are safety
checked. I also need to demonstrate my ability to use a calorimeter and
associated equipment to obtain data to determine, analyse, and evaluate the
rate of cooling of substances. I am going to present evidence of my practical
skills analysis and evaluation in a report.
Calorimetry is the scientific investigation using a calorimeter to measure
changes in state, phase, and chemical reactions in terms of heat energy
transferred.
In this assignment I used a cooling curve to determine the rate of cooling of
substances. I obtained data using the equipment provided to construct cooling
curves, analysed the rate of cooling of substances from recorded data, and
evaluated the accuracy of the practical. Moreover, I also calibrated the
thermometers, alcohol, mercury, and digital thermometers. Calibrating
thermometers updates the indications and therefore allowed me to maintain
accurate, reliable, and consistent results when taking temperatures.
Risk assessments:
, Broken glassware safety assessment: Glass is medium hazard (can cause cuts)
Typical measures to reduce risk: Wear safety goggles and gloves. Keep
glassware at the centre of the workspace/table.
Emergency action: if you notice a glass shard has penetrated the skin, use
tweezers cleaned with rubbing alcohol to remove the glass.
Hot water: Hot water is a low hazard (Can cause skin irritation)
Typical measures to reduce risk: Wear safety gloves and goggles. Stir mixtures
to allow for an even distribution of heat.
Emergency action: if the hot water comes in contact with the skin, wash with
cold water to prevent burns.
Paraffin wax safety assessment: Wax is low hazard (can cause irritation)
Typical measures to reduce risk: Ensure to use the smallest amount of the
substance. Make sure to wear eye protection. Make sure the room is well
ventilated.
Emergency action: if it comes in contact with the eyes, wash the eyes with
water repeatedly.
Stearic acid safety assessment: The acid is an irritant
Typical measures to reduce risk: Ensure the room is well ventilated. You also
need to place the acid in the middle of the table to decrease the chance of
spillages. Wear eye protection (safety goggles)
Emergency action: if the acid comes in contact with the skin remove the
contaminated clothing and then wash the skin with water.
Calibration of thermometers:
Thermometers measure temperature and not heat. Heat is a form of energy
measured in joules whereas temperature is the measure of how hot something
is in degrees Celsius (°C).
Equation relating energy, temperature and heat:
Q=mc∆T
