Question

which two conditions can limit the usefulness of the kinetic-molecular theory in describing gas behavior?

• low pressure and low temperatures
• low pressure and medium temperatures
• high pressure and medium temperatures
• high pressure and low temperatures

Explanation:

Analyze assumptions of Kinetic Molecular Theory

The Kinetic Molecular Theory (KMT) assumes that gas particles have negligible volume and experience no intermolecular attractive forces. These assumptions hold true under standard or high temperatures and low pressures, where particles are far apart and moving rapidly.

Identify conditions causing deviations

At high pressures, gas particles are forced close together, making their individual molecular volumes significant relative to the total container volume. At low temperatures, particles move slowly, allowing intermolecular attractive forces to significantly influence their behavior.

Determine the limiting conditions

Therefore, the usefulness of KMT is limited under conditions of high pressure and low temperature, where real gases deviate significantly from ideal behavior.

Answer:

• low pressure and low temperatures
• low pressure and medium temperatures
• high pressure and medium temperatures
• high pressure and low temperatures (Correct answer)