Chemical and Physical Properties of Matter

• Chemistry studies the properties, composition, and behavior of matter.
• Matter has mass and occupies space.
• Sound, light, and heat are forms of energy, not matter.
• Mass measures the amount of matter in something.

Extensive Properties

• Extensive properties depend on the quantity of material.
• Examples of extensive properties: mass, volume, length, and weight.

Intensive Properties

• Intensive properties do not depend on the amount of material.
• Boiling point, melting point, density, luster, and color are examples of intensive properties.

Physical Properties

• Physical properties can be observed or measured without changing the substance's identity.
• Examples of physical properties: density, color, odor, melting point, and boiling point.
• A change of state or form is considered a physical change.

Chemical Properties

• Chemical properties relate to a substance's ability to react, which alters its identity
• Examples of chemical properties: flammability, toxicity, reactivity, and ability to oxidize.
• Chemical properties are evident through chemical reactions or lack thereof.

Practice Examples (Properties)

• The temperature of something is intensive
• Thermal energy is extensive
• Density is intensive
• Malleability is intensive
• Conductivity is intensive
• Distance is extensive
• Price is intensive
• Total cost is extensive

Practice Examples (Changes)

• Cooking is chemical change
• Digestion is chemical change
• Mixing is physical
• Dew forming is physical
• Salt evaporation is physical
• Burning is chemical
• Rusting is chemical

States of Matter

• States of matter are the physical forms matter can take under different conditions.
• Phases are uniform regions with constant physical and chemical properties.
• Solid, liquid, gas, and plasma are primary phases.

Kinetic Energy

• Kinetic energy is the energy of motion, defined as KE = ½ mv².
• Greater speed or mass results in greater kinetic energy.
• Translation has the most kinetic energy. Vibration, rotation, and translation are types of motion of particles.

Intermolecular Forces

• Solids have strong attractions and mostly vibrate.
• Liquids have intermediate attractions and vibrate and rotate.
• Gases have weak attractions and vibrate, rotate, and translate.

States of Matter Characteristics

• Solids have fixed shapes and volumes, strong attractive intermolecular forces, and are incompressible.
• Liquids adopt the shape of their container, have a fixed volume, moderate attractive forces, and are nearly incompressible.
• Gases adopt the shape and volume of their container, have weak attractive forces, and are compressible.

Phase Transitions

• Matter changes phases with temperature or pressure changes.
• Melting: solid to liquid.
• Evaporation: liquid to gas.
• Condensation: gas to liquid.
• Freezing: liquid to solid.
• Sublimation: solid to gas.
• Deposition: gas to solid.

Energy and Phase Changes

• Adding heat increases kinetic energy, leading to phase transitions toward gas.
• Releasing energy decreases kinetic energy, leading to phase transitions toward solid.
• Plasma is created under extreme heat conditions.

Triple Point

• A triple point is a pressure-temperature combination where three phases coexist.
• Water's triple point is at 0.01°C and 0.8 atm.

Supercritical Fluids (SCF)

• Supercritical fluids exist at high temperatures and pressures, exceeding the critical point.
• They diffuse through solids like gases but dissolve substances like liquids.
• They are used as extraction agents, such as in dry cleaning.

Energy Changes

• In an endothermic process the system gains energy from the surroundings.
• In an exothermic process the system loses energy to the surroundings.

Phase Change Diagram

• Illustrates the relationship between temperature, heat energy, and phase transitions.
• Temperature remains constant during phase changes as energy breaks intermolecular forces.

Temperature and Heat

• Temperature measures the average kinetic energy of particles.
• Heat is the transfer of kinetic energy from hot to cold objects.
• Heat energy flows from hot to cold (Second Law of Thermodynamics).

Latent Heat

• Latent heat is the energy involved in phase transitions.
• During melting temperature remains constant, energy is used to allow particles to flow.
• Two phases (solid + liquid mixture) coexist.
• During boiling temperature remains constant.
• Two phases (liquid + gas mixture) coexist as energy is still needed to allow particles to translate.