Chemistry Review: States of Matter & Kinetic Theory

Flashcards covering states of matter, phase changes, kinetic molecular theory, and related definitions from the lecture notes.

What are the defining characteristics of a solid in terms of volume and shape?

A solid has both definite volume and definite shape.

How does a liquid's volume and shape behave?

A liquid has a definite volume but no definite shape, taking the shape of its container.

Describe the volume and shape of a gas.

A gas has neither definite volume nor definite shape, as it expands to fill whatever space it's in.

What is evaporative cooling?

Evaporative cooling occurs when the highest energy liquid particles leave, causing the remaining liquid to become cooler.

How does evaporation differ from vaporization?

Evaporation happens at the surface and at any temperature, while vaporization occurs throughout the liquid and only at the boiling point.

What makes hydrogen bonds in water particularly strong?

Water molecules have particularly strong hydrogen bonds because of an oxygen atom outside with three hydrogen bonds.

Name three examples of amorphous solids.

Glass, plastic, and rubber are examples of amorphous solids.

What happens to particles during freezing?

During freezing, particles lose energy, move less, and intermolecular forces pull them into a fixed position.

What causes a substance to melt?

A substance melts when particles gain kinetic energy, vibrate more, and forces weaken, allowing particles to move past each other.

Why do ionic bonds in solids require more energy to break?

Ionic bonds are much stronger, requiring more energy to break them.

What is deposition? Provide an example.

Deposition is the phase change from gas to solid, such as frost forming.

What is sublimation? Provide an example.

Sublimation is the phase change from solid to gas, such as dry ice.

During a phase change, where does the energy go?

During a phase change, energy goes into breaking or forming intermolecular forces, not into raising particle speed (temperature).

Name the phase changes that release energy.

Freezing, condensation, and deposition are phase changes that release energy.

What is the triple point?

The triple point is the temperature where gas, solid, and liquid co-exist in equilibrium.

According to the kinetic molecular theory, what happens during collisions between gas molecules?

Collisions between gas molecules are completely elastic, meaning kinetic energy is transferred without loss from one particle to another.

What is the relationship between the kinetic energy of a gas and its temperature?

The kinetic energy of a gas increases proportionally as its temperature increases.

What is an allotrope?

An allotrope is one of two or more distinct molecular forms of the same element in the same physical state.

How are particles arranged in a crystal?

In a crystal, particles are arranged in an orderly 3-dimensional pattern.

Define diffusion.

Diffusion is the movement of particles from an area of high concentration to an area of low concentration.

What is plasma?

Plasma is an ionized gas with free-moving electrons and ions.

What is vapor pressure?

Vapor pressure is the pressure made by gas when it is in balance with a liquid in a closed container.

Define viscosity.

Viscosity is a measure of the resistance of a liquid to flow.

Describe the strength of intermolecular forces in solids, liquids, and gases.

Intermolecular forces are very strong in solids, weaker in liquids, and very weak or non-existent in gases.

How does intermolecular force strength relate to the fixed shape and volume of solids?

Very strong intermolecular forces pack particles tightly together, causing solids to have a fixed shape and volume.

Compare the compressibility of solids, liquids, and gases.

Solids are not compressible, liquids are slightly compressible, and gases are very compressible.

Why are gases highly compressible?

Gases are highly compressible because their molecules are very far apart, making it easy to reduce the empty space between them.

According to the Kinetic Molecular Theory, how are gas molecules described?

Gas molecules are very far apart, in constant rapid motion, and possess kinetic energy.