Atomic Structure and the Periodic Table
Atomic number = number of protons (defines the element). Mass number = protons + neutrons. Isotopes = same element (same protons), different neutrons → same chemical properties, different mass.
Periodic table: - Periods (rows): same number of electron shells. - Groups (columns): same number of valence electrons → similar chemical properties. - Noble gases (Group 18, far right): full valence shells → very unreactive. - Metals (left) → metalloids (diagonal) → nonmetals (right).
Other concepts in General Science
- Cell Biology
- Cell Division
- Photosynthesis and Cellular Respiration
- Genetics and Heredity
- Osmosis and Diffusion
- Human Body Systems
- Taxonomy (Classification of Life)
- Ecology
- Chemical Bonding
- Acids, Bases, and pH
- States of Matter and Phase Changes
- Waves, Sound, and Light
- Earth and Space Science
- Newton's Laws of Motion