1. Tardigrade
  2. Question
  3. Chemistry
  4. A gas, which obeys Boyle's law, Charle's law, Avogadro's law etc., or ideal gas equation PV = nRT under all conditions of temperature and pressure, is called ideal gas. No gas is ideal. All gases are real gases. The real gas obeys these gas laws only when the temperature is high or pressure is low. The extent of derivations of a real gas form ideal behaviour is expressed in terms of compressibility factor Z defined as Z =( PV / nRT ) Real gases have characteristic temperatures like critical temperature, inversion temperature and Boyle temperature. These temperatures can be calculated using van der Waal constants. The compressibility factor of a gas is less than unity at STP. Therefore

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Q. A gas, which obeys Boyle's law, Charle's law, Avogadro's law etc., or ideal gas equation $PV = nRT$ under all conditions of temperature and pressure, is called ideal gas. No gas is ideal. All gases are real gases. The real gas obeys these gas laws only when the temperature is high or pressure is low. The extent of derivations of a real gas form ideal behaviour is expressed in terms of compressibility factor $Z$ defined as $Z =\frac{ PV }{ nRT }$
Real gases have characteristic temperatures like critical temperature, inversion temperature and Boyle temperature. These temperatures can be calculated using van der Waal constants.
The compressibility factor of a gas is less than unity at STP. Therefore

States of Matter

Solution:

Ideal gas equation is $PV = n RT$.
For $1$ mole of gas
$PV _{ m } = RT $
$V _{ m } =\frac{ RT }{ P }$
$Z =\frac{ PV }{ nRT }=\frac{ PV _{ m }}{ RT }$
$V _{ m }= Z RT =22.4$ lit for ideal gas at STP and $Z =1$
$V _{ m }<22.4$ lit when $Z$ is less than unity.