States of Matter: Freezing, Melting, Evaporation

• Matter exists in three states: solid, liquid, and gas
• State changes are influenced by temperature and pressure

Freezing

• Liquid water transforms into solid ice when placed in a freezer
• The process of a liquid changing to a solid is freezing
• The freezing point is the temperature at which freezing occurs
• Water's freezing point is 0 degrees Celsius

Melting

• Ice cubes absorb heat from warmer air outside a freezer and melt
• Melting is the process of a solid changing into a liquid
• The melting point of ice is 0 degrees Celsius

Evaporation

• Heating water on a stove causes it to boil
• Bubbles form in boiling water, rise, and escape as steam or water vapor
• Evaporation is the process of a liquid changing to a gas
• Water's boiling point is 100 degrees Celsius

Condensation

• Hot shower water evaporates in a closed bathroom
• Water vapors cool upon contact with cooler surfaces like mirrors, forming liquid water droplets
• Water vapors from hot seas or rivers rise, cool, and form clouds in the sky
• Condensation is the process of a gas changing to a liquid

Sublimation

• Dry ice changes directly into gas without becoming liquid
• Snow can also change directly into gas in winter without melting
• Sublimation is the process of solids changing directly into gases

Deposition

• Deposition is the reverse of sublimation
• A gas changes into a solid directly without passing through the liquid state during deposition
• Snow forms in clouds and frost forms on windows through deposition

Plasma

• Plasma is another state of matter
• Plasma occurs when gas is heated to very high temperatures
• The sun consists mostly of plasma
• Lightning or thunderbolts create plasma