Chemical Bonding Types

Study Notes

Formed between two atoms with a large difference in electronegativity (>1.7)
One atom loses an electron(s) to become a cation, while the other atom gains an electron(s) to become an anion
Electrostatic attraction between the oppositely charged ions holds them together
Typically forms between a metal and a nonmetal
Example: NaCl (sodium chloride), CaO (calcium oxide)

Formed between two atoms with a similar electronegativity (<1.7)
Atoms share one or more pairs of electrons to form a bond
Can be polar or nonpolar, depending on the difference in electronegativity
Can be single, double, or triple bonds, depending on the number of shared electron pairs
Typically forms between two nonmetals
Example: H2 (hydrogen), O2 (oxygen), CO2 (carbon dioxide)

A way to represent the valence electrons of an atom and the bonds it forms
Uses dots to represent electrons and lines to represent bonds
Octet rule: atoms tend to gain, lose, or share electrons to achieve a full outer energy level of 8 electrons
Can be used to predict the shape of a molecule and the type of bonds it forms

The arrangement of electrons in an atom's energy levels
Energy levels are divided into subshells, which are further divided into orbitals
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
Electron configuration determines the chemical properties of an element

The periodic table is arranged in a way that elements with similar properties and electron configurations are placed in the same group
Periodic trends occur due to the change in electron configuration and atomic size across a period or group
Trends include:
- Atomic radius: decreases from left to right across a period, increases from top to bottom within a group
- Electronegativity: increases from left to right across a period, decreases from top to bottom within a group
- Ionization energy: increases from left to right across a period, decreases from top to bottom within a group
- Reactivity: increases from left to right across a period, decreases from top to bottom within a group

Ionic bonds form when two atoms have a large electronegativity difference (>1.7)
A cation forms when one atom loses an electron(s), and an anion forms when the other atom gains an electron(s)
Electrostatic attraction between the oppositely charged ions holds them together
Typically forms between a metal and a nonmetal
Examples of ionic compounds include NaCl (sodium chloride) and CaO (calcium oxide)