Atomic Structure Basics

Atomic Structure

• An atom consists of three main parts:
  • Protons: positively charged particles in the nucleus (center)
  • Neutrons: particles with no charge in the nucleus
  • Electrons: negatively charged particles orbiting the nucleus
• Atomic number (Z): number of protons in an atom's nucleus, which determines the element
• Mass number (A): total number of protons and neutrons in an atom's nucleus

Electron Configurations

• Electron shells: energy levels around the nucleus where electrons occupy
  • Shells are divided into subshells (s, p, d, f) with specific capacities
• Aufbau principle: electrons occupy the lowest available energy level
• Pauli's exclusion principle: no two electrons in an atom can have the same set of quantum numbers
• Hund's rule: electrons occupy degenerate orbitals with parallel spin before pairing up

Atomic Interactions

• Electromagnetic force: attraction between oppositely charged particles (protons and electrons)
• Strong nuclear force: attraction between protons and neutrons in the nucleus
• Weak nuclear force: responsible for certain types of radioactive decay
• Ionization energy: energy required to remove an electron from an atom
• Electron affinity: energy released when an electron is added to an atom

Quantum Mechanics

• Wave-particle duality: electrons exhibit both wave-like and particle-like behavior
• Heisenberg's uncertainty principle: impossible to know both position and momentum simultaneously
• Schrödinger equation: mathematical equation describing the behavior of electrons in an atom
• Orbitals: probability distributions of electrons in an atom

Spectroscopy

• Atomic spectra: patterns of light emitted or absorbed by atoms
• Emission spectra: light emitted when electrons transition to a lower energy state
• Absorption spectra: light absorbed when electrons transition to a higher energy state
• Spectral lines: specific wavelengths of light corresponding to energy transitions

Atomic Structure

• An atom consists of three main parts: protons, neutrons, and electrons
• Protons are positively charged particles in the nucleus (center) of an atom
• Neutrons have no charge and are found in the nucleus
• Electrons are negatively charged particles that orbit the nucleus

Atomic Number and Mass Number

• Atomic number (Z) is the number of protons in an atom's nucleus, determining the element
• Mass number (A) is the total number of protons and neutrons in an atom's nucleus

Electron Configurations

• Electron shells are energy levels around the nucleus where electrons occupy
• Shells are divided into subshells (s, p, d, f) with specific capacities
• Aufbau principle: electrons occupy the lowest available energy level
• Pauli's exclusion principle: no two electrons in an atom can have the same set of quantum numbers
• Hund's rule: electrons occupy degenerate orbitals with parallel spin before pairing up

Atomic Interactions

• Electromagnetic force: attraction between oppositely charged particles (protons and electrons)
• Strong nuclear force: attraction between protons and neutrons in the nucleus
• Weak nuclear force: responsible for certain types of radioactive decay
• Ionization energy: energy required to remove an electron from an atom
• Electron affinity: energy released when an electron is added to an atom

Quantum Mechanics

• Wave-particle duality: electrons exhibit both wave-like and particle-like behavior
• Heisenberg's uncertainty principle: impossible to know both position and momentum simultaneously
• Schrödinger equation: mathematical equation describing the behavior of electrons in an atom
• Orbitals: probability distributions of electrons in an atom

Spectroscopy

• Atomic spectra: patterns of light emitted or absorbed by atoms
• Emission spectra: light emitted when electrons transition to a lower energy state
• Absorption spectra: light absorbed when electrons transition to a higher energy state
• Spectral lines: specific wavelengths of light corresponding to energy transitions

Learn the fundamental components of an atom, including protons, neutrons, and electrons, and understand atomic number and mass number. Explore electron shells and configurations.