Role of gas laws in elucidating the concept of the molecule


A wonderful thing to know about gases is that, in spite of the extensive chemical properties’ difference, all of the gases anyhow obey Gas Laws. The gas laws manage what’s the behavior of gases w.r.t. Pressure, temperature, volume, and amount.

Basically, there are 5 gas laws!

The gas laws primarily consist of thee laws, which are: Boyle’s Law, Charles’ Law, and Avogadro’s Law. All these laws were later combined into Ideal Gas Law and General Gas Equation.


Why Gas Laws are important?

Gas laws play a significant role as these laws can be used for determining the important parameters of gas’ mass by using theoretical means. For instance, if the volume and pressure of the mass of gas are recognized, then you can calculate its temperature using the Ideal Gas Equation.


Gas laws are used for?

For comparison of two different gases, these gas laws come into action. These laws are also used for determining gas properties.


Why is the ideal gas law useful?

Ideal gas law is defined as a simple equation of state which is followed by approximately by most gases, specifically at low pressures and high temperatures. The simple equation is related to P (pressure), V (volume), and T (temperature) for a fixed (n) moles number of almost any gas.


The ideal gas law is calculated as:

PV = nRT

Where n defines the number of moles; R is a constant which is called the universal gas constant and whose equal to about 0.0821 L-atm / mole-K


Rules for the use of Ideal Gas Law

  • Convert temperature (T) to kelvins (K), always.
  • Convert mass (m) to moles (mol), always.
  • Convert volume (V) to liters (L), always.
  • It is better to change the pressure to Kilopascals (kPa). Universal Gas Constant, R will be 8.314 (L.kPa)/(mol · K).


What’s the importance of combined gas law?

Combined gas law uses relationships shared by pressure, temperature, and volume: the variables which are found in other gas laws, such as Charles’ law, Boyle’s law, and Gay-Lussac’s law. For example, the temperature of refrigerated ballon reduces, the gas’s volume within the balloon reduces too.

Combining everything into one proportion

V is proportional to T divided by P

The volume of the gas given is directly proportional to the Kelvin temperature and inversely proportional to its pressure or proportional to the ratio of Kelvin temperature and its pressure.

So, a constant is put in place

PV / T = C

As the pressure increases, the temperature also increases, and it goes vice-versa.

Also, the initial and final temperatures and volumes under the condition of constant pressure can be estimated.

P1V1 / T1 = P2V2 / T2 = P3V3 / T3 etc.

The behavior of gases act in a similar manner over an extensive variety of conditions as there are molecules which are broadly spaced, and the equation of state for the ideal gas is derived from the kinetic theory. The former gas laws are examined as special ideal gas equation cases in which there are one or more than one variable are fixed.


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