1. Properties
1.1. Chemical
1.1.1. Reactivity
1.1.2. Toxicity
1.1.3. Flammability
1.1.4. Stability
1.1.5. Periodic Trends
1.1.5.1. Oxidation State
1.1.5.2. Electronegativity
1.1.5.3. Metallic Property
1.1.5.4. Ionization Energy
1.1.5.5. Electron Affinity
1.2. Physical
1.2.1. Intensive Property
1.2.1.1. Quality
1.2.1.1.1. Density
1.2.1.1.2. Color
1.2.1.1.3. Temperature
1.2.2. Extensive Property
1.2.2.1. Quantity
1.2.2.1.1. Mass
1.2.2.1.2. Volume
1.2.2.1.3. Shape
2. Changes
2.1. Chemical
2.1.1. New substance
2.1.2. Evidences
2.1.2.1. Color
2.1.2.2. Odor
2.1.2.3. Texture
2.2. Physical
2.2.1. No new substance
3. Structure
3.1. Pure Substances
3.1.1. Elements
3.1.1.1. Metal
3.1.1.2. Metalloid
3.1.1.3. Nonmetal
3.1.2. Compounds
3.1.2.1. Acid
3.1.2.2. Base
3.1.2.3. Salt
3.2. Mixtures
3.2.1. Homogeneous
3.2.1.1. Solutions
3.2.1.2. Suspensions
3.2.1.3. Colloids
3.2.2. Heterogeneous
4. Phases
4.1. Solid
4.1.1. Fixed shape
4.1.2. Little kinetic energy
4.2. Liquid
4.2.1. Fixed volume
4.2.2. No fixed shape
4.3. Gas
4.3.1. Freely moving
4.4. Plasma
4.4.1. Ionized Particles
4.4.1.1. Sun
4.4.1.2. Lightning
5. Composition
5.1. Atoms
5.1.1. Proton
5.1.2. Neutron
5.1.3. Electron
5.2. Ions
5.2.1. Positive
5.2.2. Negative
5.3. Molecules
5.3.1. Organic
5.3.1.1. Made of Carbon
5.3.2. Inorganic
5.3.2.1. No carbon