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Ch.11 - Liquids and Intermolecular Forces
Chapter 11, Problem 73g

As the intermolecular attractive forces between molecules increase in magnitude, do you expect each of the following to increase or decrease in magnitude? (g) critical temperature.

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Understand that critical temperature is the temperature above which a gas cannot be liquefied, regardless of the pressure applied.
Recognize that intermolecular forces are the forces of attraction or repulsion between neighboring particles (atoms, molecules, or ions).
Recall that stronger intermolecular forces mean that molecules are more strongly attracted to each other.
Consider that if intermolecular forces increase, it becomes easier for the substance to remain in a liquid state at higher temperatures.
Conclude that as intermolecular forces increase, the critical temperature is expected to increase, because stronger forces allow the substance to remain liquid at higher temperatures.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Intermolecular Forces

Intermolecular forces are the attractive forces that occur between molecules. These forces include hydrogen bonding, dipole-dipole interactions, and London dispersion forces. The strength of these forces influences various physical properties of substances, such as boiling and melting points, as well as critical temperature.
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Critical Temperature

Critical temperature is the highest temperature at which a substance can exist as a liquid, regardless of pressure. Above this temperature, the substance cannot be liquefied by pressure alone. The critical temperature is influenced by the strength of intermolecular forces; stronger forces typically lead to a higher critical temperature.
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Relationship Between Intermolecular Forces and Critical Temperature

As intermolecular forces increase, the critical temperature of a substance also tends to increase. This is because stronger intermolecular attractions require more energy (in the form of heat) to overcome, thus allowing the substance to remain in a liquid state at higher temperatures. Therefore, understanding this relationship is crucial for predicting changes in critical temperature.
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