Chemistry: Atomic Structure

Definition

• An atom is the smallest unit of a chemical element that retains the properties of that element.
• Atoms are the building blocks of matter and make up everything around us.

Structure

• An atom consists of three main parts:
  1. Protons: positively charged particles found in the nucleus (center) of the atom.
  2. Neutrons: particles with no charge found in the nucleus along with protons.
  3. Electrons: negatively charged particles that orbit around the nucleus.

Characteristics

• Atomic Number: the number of protons in an atom's nucleus, unique to each element.
• Atomic Mass: the total number of protons and neutrons in an atom's nucleus.
• Isotopes: atoms of the same element with different numbers of neutrons, resulting in different atomic masses.
• Ions: atoms that have gained or lost electrons, resulting in a positive or negative charge.

Electron Configuration

• Energy Levels: electrons occupy specific energy levels or shells around the nucleus.
• Valence Electrons: electrons in the outermost energy level, involved in chemical bonding.
• Electron Spin: electrons can spin clockwise or counterclockwise, influencing chemical bonding.

Atomic Models

• Rutherford Model: a planetary model with a small, dense nucleus surrounded by electrons.
• Bohr Model: an extension of the Rutherford model, with electrons occupying specific energy levels.
• Quantum Mechanical Model: a modern model that describes electrons as probability distributions around the nucleus.

Definition of Atom

• Atoms are the smallest units of a chemical element that retain the element's properties.
• Atoms are the building blocks of matter, making up everything around us.

Structure of Atom

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

Characteristics of Atoms

• Atomic Number is the number of protons in an atom's nucleus, unique to each element.
• Atomic Mass is the total number of protons and neutrons in an atom's nucleus.
• Isotopes are atoms of the same element with different numbers of neutrons, resulting in different atomic masses.
• Ions are atoms that have gained or lost electrons, resulting in a positive or negative charge.

Electron Configuration

• Energy Levels are the specific energy levels or shells that electrons occupy around the nucleus.
• Valence Electrons are electrons in the outermost energy level, involved in chemical bonding.
• Electron Spin is the ability of electrons to spin clockwise or counterclockwise, influencing chemical bonding.

Atomic Models

• Rutherford Model is a planetary model with a small, dense nucleus surrounded by electrons.
• Bohr Model is an extension of the Rutherford model, with electrons occupying specific energy levels.
• Quantum Mechanical Model is a modern model that describes electrons as probability distributions around the nucleus.