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Gas laws are fundamental rules of thumb that describe the relationship between pressure, temperature, volume, and amount of a given gas in a given container. Gas laws are the foundation of all of physics. They were first discovered experimentally by Robert Boyle, who noticed that when he kept a volume of air at a constant temperature, its pressure varied when its volume was changed.
The laws can be used to explain a wide range of phenomena, including the way gases expand when they are heated, the way their density changes when they are compressed, and their tendency to become less dense as they are heated up. The laws are sometimes referred to as the laws of thermodynamics since they are closely related to the concept of energy.
Gas laws
The laws that describe how gases behave are known as gas laws. The gas laws explain how gases behave when they’re confined to a small space, when they’re expanded, when they’re mixed, and when they’re heated or cooled. The gas laws are a group of statements that relate to each other and can be used to predict what will happen to gases when they’re manipulated in certain ways.
The four most commonly studied gas laws are the gas laws of Boyle, Charles’s Law, Avagadro’s Law, and Gay-Lussac law.
Boyle’s Law
The law of Boyle is a physical law that describes the relationship between the pressure and volume of a given mass of a gas. The volume of a given mass of a gas is inversely proportional to the pressure applied to that mass. The pressure of a gas is the amount of force per unit area that acts upon the gas. The volume of a gas is the amount of space that contains a given mass of a gas.
P1V1 =P2V2
P1 = first pressure
P2 = second pressure
V1 = first volume
V2 = second volume
Charles’s Law
The relationship between pressure and volume in gas is known as Charles’s law. The law states that the volume of a gas is inversely proportional to the pressure exerted on it. This means that if we increase the pressure on a gas, its volume will decrease. Conversely, if we reduce the pressure on a gas, its volume will increase.
V2/V1=T2/T1
Gay-Lussac’s Law
Gay-Lussac’s Law states that the pressure, P, at a certain temperature, T, is the same for any fixed volume, V, of gas. It is a fundamental property of gases that their pressure, P, depends only on their temperature, T, and not on their volume, V. For a given temperature, the volume of a given volume of gas will always contain the same number of molecules. This is true regardless of the gas’s physical state, such as its pressure or its temperature. The pressure is directly proportional to the temperature and it is inversely proportional to the volume.
P ∝ T Or P/T = k
Avagadro’s Law
Avogadro’s Law is a variation on Boyle’s Law that only applies to small volumes and low pressures. It states that the number of molecules in a small volume of gas is proportional to the total pressure of the gas and the total number of molecules in the container. This means that if you double the pressure in a small volume, the number of molecules in the gas does not double. This is, of course, a much more complicated equation than Boyle’s Law, but it also describes a fundamental aspect of gas behavior at very small scales.
V ∝ n Or V/n = k
Avogadro’s Law is referred to as PV=nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is the temperature in Kelvins.
The mathematical expression of Gay-Lussac’s Law
Gay-Lussac’s Law is a mathematical corollary of Boyle’s Law. It states that the pressure and temperature of a fixed volume of gas remain constant at a constant temperature, regardless of the amount of gas present. This means that the amount of gas does not affect the temperature or pressure of the gas in the container. This is sometimes simplified to “the pressure is the same in a closed container”, which is a slightly more accurate statement but not entirely correct.
In a paper published in 1805, Joseph-Antoine Gay-Lussac derived the following mathematical expression of Gay-Lussac’s Law to describe the relationship between the pressure and temperature of a gas in an idealized system: P = RT.
mathematical expression
P1/T1=P2/T2
Conclusion
The gas laws are equations that describe the relationship between pressure, temperature, volume, and amount of a given gas in a given container. The most famous of these is probably Boyle’s Law, which states that when the pressure of a given volume of a gas is increased, the temperature of the gas remains constant. In other words, the pressure of a fixed volume of gas will always produce the same temperature, regardless of the surrounding environment.
