Understanding Phase Changes

What is a phase change?

• A phase change is a chemical reaction.

• A phase change is the mixing of different substances.

• A phase change is the transition of a substance between different states of matter.

• A phase change is the process of heating a substance.

Name the three states of matter.

• plasma

• vapor

• mist

• solid, liquid, gas

Explain the process of evaporation.

• Evaporation is the transformation of liquid water into vapor due to energy absorption by surface molecules.

• Evaporation is the absorption of heat by solid materials to become gas.

• Evaporation occurs when vapor condenses into liquid water.

• Evaporation is the process of turning solid ice into liquid water.

Describe what happens during condensation.

• Condensation is the transformation of solid ice directly into vapor.

• Condensation is the process where water vapor cools and transforms into liquid water.

• Condensation occurs when liquid water heats up and turns into gas.

• Condensation is the process of water evaporating into vapor.

How do solids differ from liquids?

• Solids can flow and take the shape of their container; liquids have a fixed shape.

• Solids have a fixed shape and volume; liquids have a definite volume but take the shape of their container.

• Solids are always lighter than liquids; liquids are always heavier than solids.

• Solids have a definite volume but can change shape; liquids have a fixed shape and volume.

What are the characteristics of gases?

• Gases have no fixed shape or volume, are compressible, expand to fill their container, and have low density.

• Gases are not compressible and have high density.

• Gases do not expand to fill their container.

• Gases have a definite shape and volume.

Illustrate the melting process with an example.

• The condensation of steam into water.

• The freezing of water into ice.

• The melting of ice into water.

• The evaporation of water into steam.

What occurs during freezing?

• Freezing happens when a gas condenses into a liquid without temperature change.

• Freezing is the process of a solid evaporating into a gas.

• Freezing occurs when a solid turns into a liquid as it gains heat.

• Freezing occurs when a liquid turns into a solid as it loses heat.

How does temperature affect phase changes?

• Temperature has no effect on phase changes.

• Temperature influences phase changes by altering the energy of particles, facilitating transitions between solid, liquid, and gas states.

• Higher temperatures always result in solid states.

• Phase changes occur only at absolute zero temperature.

Can you give an example of condensation in everyday life?

• Fog in the morning air.

• Water droplets on a cold glass.

• Ice forming on a lake.

• Steam rising from a kettle.