Ideal gas equation is one of the important question in physics and chemistry subject in grade 11. we can also say that this is one of the fix question in physics or chemistry exam. Ideal gas is related to the Volume(v), Pressure (p), No of moles (n) and Temperature (t). It combines Boyle's law, Charle's Law and Avogadro's Law. In other word A gas which obeys all three laws i.e. Boyle's law, Charle's Law and Avogadro's Law is called ideal gas.
Simply Ideal Gas Equation is
PV=nRT
Where,
P=Pressure of the gas
V=Volume of the gas
n=No.of moles of the gas
R=Universal gas constant (R=8.314J mol^-1 K^-1 ; Note: if pressure is given in Pa and volume in m^3)
(R=0.0821L atm mol^-1K^-1; Note : if pressure is given in atm and volume given in liters
T=Absolute Temperature
DERIVATION ; PV=nRT
We can derive this equation PV=nRT by using three different law which are Boyle's law, Charle's Law and Avogadro's Law.
Now,
According to the boyle's law Volume(v) is inversely proportional to the Pressure(p) of the gas at constant temperature (t) and no. of moles (n). Boyle's law was discovered by very famous scientist Robert Boyle in 1662. Volume of gas is inversely proportional to the pressure. which can written as PV= Constant. If we gas and have two different condition we can write as P1V1=P2V2. The graph of the boyle's law will be
V∝1/P at constant tempr and no. of moles
Again,
According to the charle's law volume (v) of the gas is directly proportional to the temperature (t) at constant pressure and no. of moles(n). Charles law was discovered by Jacques Charles in 1787.Volume of the gas is directly proportional to the Temperature. Which can be written as V1/T1=V2/T2. The graph of the charle's law will be
V=Volume
T=Temperature
V∝T at constant pressure and no of moles
Similarly,
According to the Avogadro's law we can write that Volume (v) of the gas is directly proportional to the no of moles (n) at constant Temperature(t) and Pressure(p). Avogadro's law was discovered by Amedeo Avogadro in 1811. Volume is directly proportional to the no of moles. Which can be written as V1/n1=V2/n2. the graph of the Avogadro's law will be
V∝n at constant Temperature and Pressure
Now,
Combining all three equations we get,
=V∝nT/P
Now
V=nRT/P ;where R is proportionality constant which value is 8.314J mol^-1 K^-1.
PV=nRT ; which is the required equation
Uses of ideal gas equation:
- Ideal gas equation is used to calculate unknown pressure, volume, temperature and no. of moles of the gas.
- It is also used to understand gas behaviour under different conditions.
- Ideal gas equation is used to derive other gas laws and molar mass calculation.
Assumption of ideal gas equations:
Understanding the Equation:
Uses of Ideal gas equation:
- Ideal gas equation is used in medical field for oxygen cylinder.
- Ideal gas equation is used for Transporting of gases with safety.
- It is also used for designing everyday equipment.
Uses of ideal gas equation in our daily life:
- The gas inside the LPG cylinder is the perfect example of ideal gas.
- Blowing air inside the balloon is another perfect example of ideal gas because you're increasing pressure and volume of it.
- Ideal gas is used by meteorologists to calculate air pressure, temperature, and volume in the atmosphere.
Here is the derivation,
Here is the simple problem related to the ideal gas equation
- What volume will 2 moles of an ideal gas occupy at 1 atm pressure and 300 K temperature?
Solution:
Given,
No of moles(n)=2mol
Pressure(P)=1atm
Temperature(T)=300K
R = 0.0821 L·atm/mol·K
now,
According to the equation,
PV=nRT
V=nRT/P
V=2×0.0821×300/1
V=0.1642×300/1
V=49.26/1
V=49.26 liters
- Lets suppose a gas with volume of 5 liters at tempr of 300 K and pressure of 2 atm. Find the no of moles on it.
No. of moles will be 0.406 mol
Note: The VVVI question for grade 11 final exam from ideal gas will be Derivation PV=nRT which is derived above and i also shared hand written page but also practice some numericals because examine can give any type of question in your paper.