Atomic Structure and Chemical Bonding Study Notes (copy)

Democritus

Ancient Greek philosopher who proposed the concept of basic constituents of all substances.

John Dalton's Atomic Theory

Proposed in 1808 that matter consists of small, indivisible particles called atoms.

Indivisibility (Dalton's vs Modern Atomic Theory)

Dalton's theory stated that atoms are indivisible, while modern theory shows atoms are divisible and consist of subatomic particles.

Isotopes

Atoms of the same element that have the same atomic number but different mass numbers.

Electron

Negatively charged subatomic particle with negligible mass compared to protons and neutrons.

Proton

Positively charged subatomic particle located in the nucleus, with a mass of approximately $1.670 \times 10^{-24}\,g$.

Neutron

Neutral subatomic particle located in the nucleus, with a mass of approximately $1.676 \times 10^{-24}\,g$.

Atomic Number (Z)

The total number of protons present in the nucleus of an atom.

Mass Number (A)

The total number of protons and neutrons in the nucleus of an atom.

Octet Rule

Atoms tend to achieve a stable electronic structure containing 8 valence electrons in their outermost shell.

Covalent Bond

A chemical bond formed by the mutual sharing of one or more electron pairs between two non-metallic atoms.

Electrovalent Bond

A chemical bond formed by the complete transfer of one or more valence electrons from a metallic atom to a non-metallic atom.

Fundamental Particles of an Atom

Protons, neutrons, and electrons are the fundamental particles that make up an atom.

Cation

A positively charged ion formed when an atom loses valence electrons.

Anion

A negatively charged ion formed when an atom gains valence electrons.

Chemical Properties of Isotopes

Isotopes of the same element have identical or similar chemical properties due to the same electronic configuration.

Physical Properties of Isotopes

Isotopes differ in physical properties such as mass due to different numbers of neutrons.

Lewis Structure

A diagram that shows the bonding between atoms of a molecule and the lone pairs of electrons.

Stable Electron Configuration

An electron configuration in which atoms achieve a full outer shell, resulting in chemical stability.

Bond Fission

The process of breaking a covalent bond, resulting in radical formation.

Radical

An atom or molecule that has unpaired electrons and is very reactive.

Planck's constant (h)

A fundamental physical constant used to describe the sizes of quanta in quantum mechanics.