Matter and Its Properties

Matter and its Properties

• Matter is anything that occupies space and has mass.
• Matter exists in three states: solid, liquid, and gas.
• Solids: Have a definite shape and volume. The shape and volume don't change regardless of the container.
• Liquids: Have a definite volume but no definite shape. The shape changes depending on the container.
• Gases: Have neither a definite shape nor a definite volume. The shape and volume change depending on the container.
• All matter is made of tiny particles that are constantly moving.

States of Matter: Particle Behavior

• In solids, particles vibrate back and forth in all directions.
• In liquids, particles slide past one another (like marbles in a box).
• In gases, particles move freely and are not close together.

Mass and Weight

• Mass: The amount of matter in an object.
• Weight: The gravitational pull on the mass of an object.

Volume

• Volume of a liquid can be measured using a graduated cylinder or measuring cup.
• For solids: use a formula for regular shapes, or the displacement method for irregular shapes.

Density

• Density is the mass per unit volume of a substance.

Additional Physical Properties

• Other important physical properties may include:
  • Magnetism
  • Malleability
  • Electrical conductivity

Melting and Boiling Point

• Melting Point: The temperature at which a solid becomes a liquid.
• Boiling Point: The maximum temperature a liquid can reach before it turns into a gas.

Solubility

• Solubility is the ability of one material to dissolve in another (e.g., powdered juice in water).

Chemical Properties

• A chemical property is the ability or inability of a substance to combine with or change into new substances.
• It is observed when a substance reacts or changes.

Flammability

• Flammability is the ability of a substance to burn easily.

Ability to Rust

• Rust forms when iron reacts with water and oxygen in the air, showing a chemical property of iron.

Identifying Matter Using Physical Properties

• Physical properties help describe and identify matter.
• Melting point and density are properties that don't depend on the size or amount of the sample.

Sorting Materials Using Properties

• Both physical and chemical properties are useful for sorting materials (e.g., storing crackers and milk).

Separating Mixtures Using Physical Properties

• Physical properties can help separate mixed matter (e.g., thawing ice cream).

Changes of Matter: Physical Change

• A physical change alters size, shape, form, or state of matter without changing its core identity.
• Examples include dissolving, and changing state (e.g., melting ice, boiling water).

Changes of Matter: Chemical Change

• A chemical change transforms substances into new substances with different properties.
• Another name for this is a chemical reaction.

Signs of Chemical Change

• Formation of gas (bubbles).
• Formation of a precipitate (a solid forming when two liquids combine).
• Color change (e.g., rusting metal).

Energy and Physical Change

• All chemical reactions involve energy changes.
• Thermal energy is often needed for reactions (e.g., cooking).

Reversibility of Changes

• Not all changes can be reversed.
  • Example: Fireworks (chemical)
  • Example: Grating a carrot (physical)
  • Example: Salt solution (physical change, reversible)

Conservation of Mass

• Physical changes do not affect the mass of matter.
• Mass is conserved in all chemical and physical changes. The mass of the substance before the change equals the mass after the change.
• Antoine Lavoisier discovered this and called it the Law of Conservation of Mass

Weight

• Weight remains the same because it depends on mass.