Ions, Ionic Bonding and the Octet Rule - Vocabulary Flashcards

A set of vocabulary-style flashcards covering ions, bonding, Lewis structures, and related concepts from the notes.

Octet Rule

Atoms tend to react in ways that allow them to achieve an outer shell of eight electrons.

Ion

An atom or group that has gained or lost electrons and carries a net charge.

Cation

A positively charged ion formed when an atom loses electrons (electron deficient).

Anion

A negatively charged ion formed when an atom gains electrons (electron rich).

Ionization

The process of removing electrons from an atom to form cations.

Ionic Bond

An electrostatic attraction between positively and negatively charged ions.

Ionic Compound

A compound composed of cations and anions held together by ionic bonds.

Lewis Symbol

A notation showing an element’s valence electrons as dots around the element symbol.

Valence Electrons

Electrons in the outermost electron shell that participate in bonding.

Empirical Formula

The simplest whole-number ratio of atoms in a compound.

Crossing Charges

A method to determine a formula unit by using ion charges as subscripts and then simplifying.

Formula Unit

The lowest whole-number ratio of ions in an ionic compound.

Transition Metal Cation Nomenclature

Transition metal cations often use Roman numerals to indicate charge (e.g., Chromium(III)).

Monoatomic Anion -ide Suffix

Monoatomic anions use the -ide suffix (e.g., chloride, oxide, sulfide).

Roman Numeral Nomenclature

Charges of cations with variable oxidation states are shown in Roman numerals after the name.

Nitrate (NO3-)

A polyatomic ion with a -1 charge consisting of nitrogen and oxygen.

Nitrite (NO2-)

A polyatomic ion with a -1 charge consisting of nitrogen and oxygen.

Sulfate (SO4^2-)

A polyatomic ion with a -2 charge consisting of sulfur and oxygen.

Hydroxide (OH-)

A polyatomic ion with a -1 charge consisting of oxygen and hydrogen.

Carbonate (CO3^2-)

A polyatomic ion with a -2 charge consisting of carbon and three oxygens.

Bicarbonate (HCO3-)

A polyatomic ion with a -1 charge consisting of hydrogen, carbon, and oxygen.

Acetate (C2H3O2-)

A polyatomic ion with a -1 charge often sourced from acetic acid.

Permanganate (MnO4-)

A polyatomic ion with a -1 charge containing manganese and oxygen.

Peroxide (O2^2-)

A diatomic anion with a -2 charge; consists of two oxygens.

Superoxide (O2-)

A diatomic anion with a -1 charge (O2^-).

Phosphate (PO4^3-)

A polyatomic ion with a -3 charge containing phosphorus and oxygen.

Hydrogen Phosphate (HPO4^2-)

A polyatomic ion with a -2 charge containing hydrogen, phosphorus, and oxygen.

Dihydrogen Phosphate (H2PO4-)

A polyatomic ion with a -1 charge containing two hydrogens, phosphorus, and oxygen.

Covalent Bonding

Bonding through the sharing of electrons between atoms.

Lewis Dot Structure

A drawing showing atoms’ valence electrons as dots and all bonds and lone pairs.

Lone Pairs

Pairs of valence electrons not involved in bonding.

Single, Double, Triple Bonds

Types of covalent bonds representing one, two, or three shared electron pairs.

Duet Rule (Hydrogen)

Hydrogen achieves stability with two electrons in its outer shell.

Expanded Octet

When a central atom has more than eight electrons around it (common for elements in period 3 and beyond).

Be Cl2 Exception

Beryllium often forms bonds with only four electrons around it (not a full octet).

BF3 Exception

Boron can have an incomplete octet (6 electrons) in BF3.

PCl5 Exception

Phosphorus may expand its octet to 10 electrons in PCl5.

SF6 Exception

Sulfur can expand its octet to 12 electrons in SF6.

Tetrahedral Geometry

Molecular geometry with bond angles of about 109.5 degrees.

Linear Geometry

Molecular geometry with bond angles of 180 degrees.

Planar Triangular (Trigonal Planar) Geometry

Molecular geometry with bond angles of about 120 degrees.