39 terms

Unit 5 Chemical Bonding

Chemical bond
the attractive force that holds atoms or ions together
Bond energy
the energy required to break the bonds in 1 mol of a chemical compound
Ionic bonding
a force that attracts electrons from one atom to another, which transforms a neutral atom into an ion
an ion that has a positive charge
an ion that has a negative charge
Ionic compound
a compound composed of ions bound together by electrostatic attraction
Monoatomic ions
ions formed from a single atom
Binary ionic compound
an ionic compound in which one element present is a metal and the other element present is a nonmetal
Formula unit
the collection of atoms corresponding to an ionic compound's formula such that the molar mass of the compound is the same as the mass of 1 mol of formula units
Oxidation numbers
the number of electrons that must be added to or removed from an atom in a combined state to convert the atom into the elemental form
Polyatomic ions
ions that are made of more than one atom
Covalent bonding
chemical bonding that results from the sharing of electron pairs between two atoms
Polar covalent bond
a covalent bond in which a pair of electrons shared by two atoms is held more closely by one atom
Diatomic molecules
molecules made up of two atoms of the same element
Nonpolar covalent bond
a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge
a molecule or a part of a molecule that contains both positively and negatively charged regions
Electronegativity difference
The difference in electronegativity between two elements in a bond.
the smallest particle (one or more atoms) of a substance that has all the properties of that substance
Molecular compound
a chemical compound whose simplest units are molecules
Chemical formula
a combination of chemical symbols and numbers to represent a substance
Binary molecular compound
These are composed of two non metallic elements, and prefixes are used to denote the number of atoms of each element.
Binary acid
an acid that does not contain oxygen, such as hydrofluoric acid
an acid that is a compound of hydrogen, oxygen, and a third element, usually a nonmetal
compounds that have a specific number of water molecules attached to them
Octet rule
States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons
Lewis structure
a structural formula in which electrons are represented by dots; dot pairs or dashes between two atomic symbols represent pairs in covalent bonds.
VSEPR theory
a theory that predicts some molecular shapes based on the idea that pairs of valence electrons surrounding an atom repel each other.
Molecular polarity
is dependant on the difference in electronegativity between atoms in a complound and the asymmetry of the compound's structure
Unshared pair or lone pair of electrons
pair of electrons that is not involved in bonding and that belongs exclusively to one atom
Single covalent bond
a bond formed when two atoms share a pair of electrons
Double covalent bond
A type of covalent bond in which two atoms share two pairs of electrons; symbolized by a pair of lines between the bonded atoms.
Triple covalent bond
a bond formed by sharing three pairs of electrons
Expanded valence
Elements surrounded by more than 8 electrons when they combine with the highly electronegative elements
Resonance structure
a structure that occurs when it is possible to draw two or more valid electron dot structures that have the same number of electron pairs for a molecule or ion
Covalent network bonding
atoms that are covalently bonded together throughout the smaple example diamonds, quartz, graphite
Metallic bonding
a bond formed by the attraction between positively charged metal ions and the electrons around them
Dipole-dipole forces
attractions between oppositely charged regions of polar molecules
Hydrogen bonding
the intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule
London dispersion forces
the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles