Chemistry: Kinetic Molecular Theory of Gases

kinetic molecular theory of gases

It is a model that explains the behavior and properties of gases in terms of the motion and interactions of their molecules.

kinetic molecular theory of gases

This theory is based on several key postulates that help us understand gas behavior at the microscopic level.

• gas composition

• no intermolecular forces

• elastic collisions

• continuous random motion

• average kinetic energy and temperature

What are the five key postulates of the kinetic molecular theory?

gases

These consist of a large number of tiny particles (molecules or atoms) that are in constant, random motion.

gases

These particles are far apart relative to their size, meaning the volume of the gas molecules themselves is negligible compared to the volume of the container.

no intermolecular forces

There are no attractive or repulsive forces between gas molecules.

no intermolecular forces

This means that molecules move independently of each other, except when they collide.

elastic collisions

It is when gas molecules collide with each other or with the walls of the container, the collisions are perfectly elastic.

elastic collisions

This means there is no loss of kinetic energy in the collisions; the total kinetic energy of the molecules remains constant.

continuous random motion

It is when move in straight lines until they collide with other molecules or the container walls.

kinetic energy and temperature

The average kinetic energy of gas molecules is directly proportional to the absolute temperature of the gas.

ideal gas law

It is a fundamental equation in chemistry and physics that describes the behavior of an ideal gas.

ideal gas law

This law combines several empirical laws into a single equation and provides a good approximation for the behavior of real gases under many conditions.

boyle’s law

This law states that the pressure (𝑃) of a gas is inversely proportional to its volume (𝑉) when the temperature and the number of gas molecules are held constant.

boyle’s law

It is the relationship between pressure and volume at a constant temperature.

boyle’s law

If the volume of a gas decreases, its pressure increases, provided the temperature remains constant.

gay-lussac’s law

It is the relationship between pressure and temperature at constant volume.

gay-lussac’s law

It states that the pressure (𝑃) of a gas is directly proportional to its absolute temperature (𝑇) when the volume and the number of gas molecules are held constant.

gay-lussac’s law

If the temperature of a gas increases, its pressure increases, provided the volume remains constant.

charles’ law

It is the relationship between volume and temperature at constant pressure.

charles’ law

It states that the volume (𝑉) of a gas is directly proportional to its absolute temperature (𝑇) when the pressure and the number of gas molecules are held constant.

charles’ law

If the temperature of a gas increases, its volume increases, provided the pressure remains constant.

combined gas law

This lawmerges Boyle's, Charles's, and Gay-Lussac's laws into a single equation

ideal gas law

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boyle’s law

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charles’ law

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gay-lussac’s law

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combined gas law

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