Chapter 4 & 5 – Chemical Bonding and Properties of Materials

Includes terms and definitions such as Noble gases, Duplet, Octet, Chemical bonding, Ion, Cation, Anion, Ionic bond, Criss-cross method, LCM method, Covalent bond, Molecule, Ionic compound, Naming rules (-ide, -hydroxide, -ate), Valence electrons, Dot-and-cross diagram, Ammonium ion, etc.

Noble gases

Group 18 elements with fully filled valence shells; unreactive and stable

Duplet

2 valence electrons (e.g. Helium)

Octet

8 valence electrons (e.g. Neon, Argon)

Chemical bonding

Process of gaining, losing, or sharing electrons to achieve noble gas configuration

Ion

A charged particle formed when atoms lose/gain electrons

Cation

Positively charged ion (metal loses electrons)

Anion

Negatively charged ion (non-metal gains electrons)

Ionic bond

Electrostatic force between oppositely charged ions

Criss-cross method

A method to find ionic compound formula by swapping ion charges

LCM method

A method using least common multiple to balance charges in ionic compounds

Covalent bond

A bond formed by sharing of electrons between non-metal atoms

Molecule

A group of atoms held together by covalent bonds

Ionic compound

Compound formed by ions with equal total positive and negative charges

Naming rule (-ide)

Used when compound contains only two elements (e.g., sodium chloride)

Naming rule (- hydroxide)

Used when compound contains hydroxide ion (e.g., calcium hydroxide)

Naming rule (-ate)

Used when compound contains a polyatomic ion with oxygen (e.g., copper(II) sulfate)

Valence electrons

Electrons in the outermost shell of an atom

Dot-and-cross diagram

Diagram used to show electron transfer/sharing during bonding

What I need, I share

Principle used in covalent bonding

Ammonium ion (NH₄⁺)

A polyatomic cation made of covalently bonded non-metals