Atomic Structure, Electronic Configuration, and Chemical Reactions

These flashcards cover key terms related to atomic structure, electronic configuration, and types of chemical reactions discussed in the lecture.

Atom

The smallest particle of an element that retains the unique properties of that element.

Protons

Positively charged particles found in the nucleus of an atom.

Neutrons

Neutral particles found in the nucleus of an atom.

Electrons

Negatively charged particles that orbit the nucleus of an atom.

Ion

An atom that has gained or lost electrons, resulting in a positive or negative charge.

Cation

A positively charged ion formed by the loss of electrons.

Anion

A negatively charged ion formed by the gain of electrons.

Atomic Number (Z)

The number of protons in an atom, which also equals the number of electrons in a neutral atom.

Mass Number (A)

The sum of the number of protons and neutrons in an atomic nucleus.

Isotope

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

Valence Electrons

Electrons that occupy the outermost energy level of an atom and determine its chemical properties.

Aufbau Principle

The principle that electrons fill the lowest energy orbitals first.

Pauli Exclusion Principle

The principle stating that no two electrons in the same orbital can have the same spin.

Hund’s Rule

The rule stating that electrons will occupy degenerate orbitals singly before pairing up.

Quantum Numbers

A set of four numbers that describe the properties of atomic orbitals and the electrons in them.

Ionic Bond

A chemical bond formed by the transfer of electrons from one atom to another, resulting in attraction between oppositely charged ions.

Covalent Bond

A bond formed by the sharing of electrons between nonmetal atoms.

Metallic Bond

The bond formed by the attraction between positively charged metal ions and the electrons around them.

Intermolecular Forces

Forces of attraction or repulsion between neighboring particles (atoms, molecules, or ions).

Chemical Reaction

A process where reactants transform into products, involving changes in energy and the movement of electrons.

Endothermic Reaction

A reaction that absorbs energy from its surroundings.

Exothermic Reaction

A reaction that releases energy to its surroundings.

Equilibrium

A state in a chemical reaction where the rates of the forward and reverse reactions are equal.

Le Chatelier’s Principle

A principle stating that if an external change is applied to a system at equilibrium, the system will adjust to counteract that change.