Question

When does a gas deviate the most from its ideal behaviour ?

• A. At low pressure and low temperature
• B. At low pressure and high temperature
• C. At high pressure and low temperature
• D. At high pressure and high temperature

Answer 1

The Correct Option is C

To understand when a gas deviates the most from its ideal behavior, we need to consider the conditions under which real gases differ from the ideal assumptions of the Ideal Gas Law.

The Ideal Gas Law assumes that gas particles have no volume and do not interact with each other. However, real gases do have particle volume and intermolecular forces.

1. High Pressure: At high pressures, gas particles are forced closer together. The volume occupied by gas particles becomes significant compared to the total volume of the gas, violating the assumption that gas particles have no volume. Additionally, intermolecular forces become significant.
2. Low Temperature: At low temperatures, gas particles have less kinetic energy, meaning they move more slowly. As a result, the attractive forces between gas particles become more pronounced, causing deviations from ideal behavior.

The conditions that lead to the greatest deviation from ideal gas behavior are those where the assumptions of the Ideal Gas Law break down. Hence, real gases deviate most from ideal behavior at high pressure and low temperature. Under these conditions, the assumptions of negligible volume and no intermolecular forces fail.

The correct answer is, therefore, the option: At high pressure and low temperature.