A gas that follows Boyle’s law, Charles law and Avogadro’s law is called an ideal gas. Under what conditions a real gas would behave ideally?


According to Boyle’s law, at constant temperature, the volume of a gas is inversely proportional to its pressure,

According to Charle’s law, Volume of the gas is directly proportional to its kelvin temperature at constant temperature,


According to Avogadro’s law, if equal number of molecule of different gases at identical temperature and pressure condition than occupy same amount of volume.


If a gas follows Boyle’s law, Avogadro’s law, Charles law. Then gas is called ideal gas. From these three gas law we get ideal gas law.


i.e.


Where, P= pressure, V = volume of the gas n= no. of mole, T= temperature


All gases are not ideal gas. Real gas doesn’t obey the gas law at normal temperature and pressure condition. Gas behaves ideally under two conditions these are - (i) the volume of molecule of a gas is negligible as compared to its complete volume. (ii) There is no attraction force between the gases.


Real gas obey these law only under limited conditions of low pressure and high temperature .At low pressure , system volume increases but volume of real gas become negligible , molecules occupy no volume relative to system .So gas behave as ideal . At high temperature gas molecules movement become fastersuch that there is no intermolecular attraction, hence real gas behave ideal.


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