Covalent Bonding and Molecular Compounds

This set of vocabulary flashcards covers the fundamental concepts of covalent bonding, electronegativity, naming conventions, and molecular mass as presented in Chapter 4: When Atoms Share Electrons.

Covalent bond

A chemical interaction that occurs when nonmetals fill their valence shells by sharing electrons with one or more other nonmetals.

Octet rule

A principle noting that atoms are most stable when their outer shells contain eight electrons.

Lewis dot structures

Diagrams representing the positions of valence electrons as dots, originally based on a cubic scheme to explain how atoms form compounds.

Molecule

The smallest particle of a covalent compound, formed when a group of atoms is joined by covalent bonds.

Electronegativity

A measure of an atom's ability to draw electrons from other atoms in a molecule toward itself.

Fluorine

The most electronegative element on the periodic table, located in the far upper right corner.

Cesium

The least electronegative element on the periodic table.

Bond energy

The energy required to break a specific chemical bond, often expressed in units of $kJ\,mol^{-1}$. It is stronger for triple bonds than for double or single bonds.

Bond length

The equilibrium distance between the nuclei of covalently bonded atoms where attractive forces and repulsive forces are balanced.

Joule

A measurement representing the energy required to move a $1\,kg$ mass $1\,m$ at an acceleration of $1\,m/sec$.

Organic molecules

Molecules containing a carbon-carbon bond or a carbon-hydrogen bond, often referred to as the molecules of life.

Inorganic molecules

Molecules that do not contain the carbon-carbon or carbon-hydrogen pairings characteristic of organic molecules, such as $O_2$, $N_2$, and $H_2O$.

IUPAC

An acronym for the International Union of Pure and Applied Chemistry, which oversees naming protocols to ensure every unique compound has a specific name.

Binary molecular compounds

Inorganic molecular compounds consisting of only two elements, typically named with the ending -ide.

Formula mass

The sum of the masses of the elements in an ionic compound formula.

Molecular mass

The sum of all the masses of the elements in a molecular formula, expressed in $g\,mol^{-1}$.

Prefixes (Naming)

Used in naming molecular compounds to indicate the number of atoms, such as mono- ($1$), di- ($2$), tri- ($3$), and tetra- ($4$).