Properties Measurement/PVT
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ABSTRACT
The name of this experiment is the Properties Measurement or PVT. This experiment demonstrates the fundamental thermodynamics processes that deal with an ideal gas. There were five separate experiments conducted with this unit which
consisted of Boyle’s Law Experiment, Gay

Lussac’s Law, the isentropic expansion,
determination of ratio volume and heat capacity. This experiment mainly focuses on the relationship of between the pressure, volume and temperature of an ideal gas. As an example of the connection between the variables; when the temperature of a gas increases, so does its pressure but when the volume increases, the pressure decreases. With the results obtained, each theory of the experiments were proven through the graph and calculations made.
INTRODUCTION
The Properties Measurement Apparatus is an apparatus used to study the fundamental processes of thermodynamics. It deals with ideal gas and can be used to understand the Law of Conservation of Energy or First Law of Thermodynamics, Second Law of Thermodynamics and the relationship between the pressure, temperature and volume of a gas. An ideal gas is a hypothetical gas which obeys the formula
PV=nRT
where P and T are the absolute pressure and absolute temperature respectively and R is the constant of the particular gas. Under a set of conditions, a real gas can also behave as an ideal gas. Apart from this equation, an ideal gas also obeys other laws such as
Boyle’s Law and Gay

Lussac’s law.
Without us knowing, the applications of these laws are used a lot more frequently in our daily lives. As an example; when inhaling, the diaphragm expands which causes the pressure within the thoracic cavity to decrease and allow air to enter as proposed through
Boyle’s Law.
Meanwhile when exhaling, the opposite occurs as the pressure within our thoracic cavity increases, allowing air to be removed from our body. Apart from that, we see that a hot air balloon is able to float above the clouds
Properties Measurement/PVT
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despite being attached to a heavy basket with loads. This was made possible by the
understanding of Charles’ Law. The heating
of air inside the balloon increases its pressure, making it greater than the surrounding atmospheric pressure which allows it to soar across the sky. The knowledge of thermodynamics and relationship of ideal gas has generated many inventions and possibilities in our world today. Therefore, it is crucial that this field of knowledge not to be studied just as a form of numbers and fact, but with our hope and enthusiasm of engineering a better tomorrow.
AIMS
Boyle’s Law Experiment
To determine the relationship between pressure and volume of an ideal gas. To determine the experimental results with theoretical results.
GayLussac Law Experiment
To determine the relationship between pressure and temperature of an ideal gas.
Isentropic Expansion Process
To demonstrate the isentropic expansion process.
Determination of ratio volume
To determine the ratio of volume and compare it with the theoretical value
Determination of ratio of heat capacity
To determine the ratio of heat capacity.
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THEORY
An ideal gas, or also called as perfect gas is a hypothetical gas whose pressure, volume, and temperature corresponds with the ideal gas law that is:
PV = nRT
Although an ideal gas is imaginary, at low pressure and high temperature, the density of a real gas decreases making it able to behave like an ideal gas. This gas abides not only the ideal gas equation of state but also
Boyle’s Law
and Gay
Lussac’s
Law.
Boyle's Law
states that the product of the pressure and volume of gas is a constant at a constant temperature. This law can be used to predict the change in pressure of the same gaseous substance after an expansion or compression in the volume.
PV = k P
1
V
1
= P
2
V
2
Graph of Boyle’s Law
From the graph, it shows that the pressure is inversely proportional to volume at a constant temperature. This is because under compression, the molecules within the confined space experiences a higher frequency of effective collision with each other as well as with the walls of the container. Vice versa, under expansion, the
Properties Measurement/PVT
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situation proceeds in the opposite direction.
GayLussac Law
or also known as
Charles’
Law states that the pressure of a gas of fixed mass and volume is directly proportional its absolute temperature.
Therefore, when comparing a same substance under two different sets of conditions, it can be written as:
P
1
T
2
= P
2
T
1
4, 2012 The graph shows the proportionality between the pressure and temperature of a gas This follows the kinetic theory which states that by increasing the temperature, the molecules gain speed which increases the frequency of effective collision An
isentropic process
is a process takes place from initiation to completion without an increase or decrease in the entropy of the system.
ΔS = 0
Or S
1
= S
2
Also, when a gas is in an this process, the ratio of temperature after the expansion and before can be calculated If a process is both reversible and adiabatic (insulated), then it is an isentropic process. An isentropic process is an idealization of an actual process, and serves as a limiting case for an actual process. The equation of a gas in an isentropic process is: