Introduction
In this experiment I will be using steric acid and paraffin wax to determine the cooling rate,
and how long it takes them to progress from a liquid to a gas and from a solid to a liquid
state from each of their melting points, checking for exothermic/endothermic effects and
calculating the heat capacity specifically (Hartley, et al, 2016). The melting point of steric
acid should be between 67-72 °C (Chemical Book, 2023), and the melting point of paraffin
wax should be between 46-68 °C (Science Direct, 2023). From these results I will be able to
see what their cooling period is and construct a cooling curve graph. These will also certain
melting points depending on how strong the bonds are between them. These are weak
bonds called that can include Van der Walls forces, dipole-dipole forces or hydrogen bonds
(Canvas, Class Notes, 2023).
The practice of measuring how much heat is produced or absorbed during a chemical
reaction is known as calorimetry. The amount of heat that changes can be used to identify
whether a reaction is exothermic (releases heat) or endothermic (absorbs heat) (LibreTexts,
2023). This can be done by using a calorimeter which is nothing more than a container, like
a glass beaker or a polystyrene cup that can be used in combination with a thermometer
during a reaction where heat is transferred (Hartley, et al, 2016). The equation I can use to
determine the amount of heat that is transferred is q=mc△T (Canvas, Class notes, 2023).
Calorimetry also plays a significant role in daily living by regulating human metabolic rates
and subsequently sustaining bodily functions including body temperature (LibreTexts, 2023).
The two types of thermometers I will be using in this experiment is the liquid filled
thermometer and an electronic thermometer. The liquid filled thermometer can contain
either alcohol in the glass, where an exact amount of alcohol is coloured and put under
pressure in a glass tube, in which it expands as the rises up the tube, or it can contain
mercury, where a specific amount of mercury is and sealed, and in the same way it expands
as the temperature rises. However, mercury reacts very swiftly to temperature changes, and
its glass is bent, allowing it easier to take measurements and therefore it a more accurate
thermometer comparing to the alcohol liquid filled one, which in this case is the one I used
(Canvas, Class Notes, 2023).
The electronic thermometer is linked to a digital display, in which there is a connection
between two wires made of different metals. As the temperature rises, a potential
difference will develop at the wire connection, and the electrical resistant will decline. Then
we have the resistance thermometer, which in this case is the one I will be using and has a
conductive wire that becomes more resistant to current flow as temperature rises. It
consists of a bi-metallic strip that is wound up and expands. It is attached to a calibrated
pointer that can read a scale, which shows figures to decimal place (Canvas, Class Notes,
2023).
Calorimetry is used in many different industries. For example, one industry that uses
calorimetry on a daily bases are pharmaceutical labs. During the development stage of a
solid drug molecule, pharmaceutical solution calorimetry is very helpful since it enables