When do gases deviate

There is some force of attraction. The graphs below represent different gases and show how they behave under high and low pressure. Figure a shows how gases behave differently from their ideal behaviour, particularly in high pressure.

At low pressure, as shown in figure b , the real gases behave more like that of the expected ideal behaviour. For gases such as CO 2 and C 2 H 4 , they deviate more than other real gases because these gases tend to liquefy at lower pressures.

Now, the graph below shows the behaviour of real gas N 2 under different temperatures. The figure shows that the real gas Nitrogen behaves more according to the ideal gas behaviour when the temperature is high. Why do gases deviate so much under high pressure and low temperature? At both the conditions, the basic assumptions that the law of the ideal gas holds, that are: the volume of the molecules of the gas are negligible and intermolecular interaction is negligible — these two become invalid.

Under low pressure, the gas molecules are farther apart from each other, and the volume of molecules is the same as the volume of the container. As the pressure increases, the molecular space contracts, and their volume becomes significant as compared to the container.

If more pressure is exerted, then the gas liquefies under very high pressure such as CO 2. All the molecules attract each other by a combination of forces.

Which one of the following alkaline earth metal sulphates has its hydration enthalpy greater than its lattice enthalpy? The s-Block Elements. The mass of copper deposited at the cathode is At. Which of the following compounds is not colored yellow? Coordination Compounds. Questions from States of Matter. The interaction between a polar and non-polar molecule is known as AMU AMU What is the pressure of the gas under these condition? But in reality this is not the case: we get errors by applying the ideal gas law.

That's why van der Waals corrected it by introducing suitable constants. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why do real gases deviate from ideal gas behavior? Asked 5 years, 2 months ago. Active 2 years, 9 months ago.

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