Atomic Structure and Models

Atomic Structure

Atomic Models

• Rutherford Model (1911): Atom consists of a small, dense nucleus surrounded by electrons orbiting at a distance.
• Bohr Model (1913): Atom consists of a nucleus surrounded by electrons in specific energy levels (shells) with specific capacities.

Subatomic Particles

• Proton:
  • Positive charge
  • Found in nucleus
  • Mass: 1 atomic mass unit (amu)
• Neutron:
  • No charge
  • Found in nucleus
  • Mass: 1 amu
• Electron:
  • Negative charge
  • Found in electron cloud
  • Mass: 1/1836 amu

Atomic Nucleus

• Proton-Neutron Ratio: The ratio of protons to neutrons in the nucleus determines the element's identity and its isotopes.
• Nuclear Stability: The number of neutrons in the nucleus affects the stability of the atom.

Electron Configuration

• Electron Shells: Energy levels around the nucleus that can hold a specific number of electrons.
• Valence Shell: The outermost energy level, involved in chemical bonding.
• 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.

Energy Levels

• Principal Energy Level (n): The main energy level, describing the distance of the electron from the nucleus.
• Azimuthal Quantum Number (l): Describes the shape of the electron's orbit.
• Magnetic Quantum Number (m): Describes the orientation of the electron's orbit.
• Spin Quantum Number (s): Describes the spin of the electron.

Ionization Energy

• Ionization Energy: The energy required to remove an electron from an atom.
• Successive Ionization Energies: The energy required to remove subsequent electrons from an atom increases.

Atomic Structure

• Atom consists of a small, dense nucleus surrounded by electrons orbiting at a distance (Rutherford Model, 1911)
• Atom consists of a nucleus surrounded by electrons in specific energy levels (shells) with specific capacities (Bohr Model, 1913)

Subatomic Particles

• Proton: Positive charge, found in nucleus, mass: 1 atomic mass unit (amu)
• Neutron: No charge, found in nucleus, mass: 1 amu
• Electron: Negative charge, found in electron cloud, mass: 1/1836 amu

Atomic Nucleus

• Proton-Neutron Ratio determines the element's identity and its isotopes
• Nuclear Stability affected by the number of neutrons in the nucleus

Electron Configuration

• Electron Shells: Energy levels around the nucleus that can hold a specific number of electrons
• Valence Shell: Outermost energy level, involved in chemical bonding
• 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

Energy Levels

• Principal Energy Level (n): Main energy level, describing the distance of the electron from the nucleus
• Azimuthal Quantum Number (l): Describes the shape of the electron's orbit
• Magnetic Quantum Number (m): Describes the orientation of the electron's orbit
• Spin Quantum Number (s): Describes the spin of the electron

Ionization Energy

• Ionization Energy: Energy required to remove an electron from an atom
• Successive Ionization Energies: Energy required to remove subsequent electrons from an atom increases