Chapter 2 - Covalent Substances Flashcards
Bond pair
pair of valence electrons that is shared between atoms in a covalent bond
Covalent bonding
bonding resulting from the sharing of electrons between non-metal atoms
Diatomic molecule
covalently bonded pair of atoms of the same or a different
non-metal element
Electrostatic attraction
attraction between opposite charges
Intramolecular bonds
bonding between atoms within a molecule
Lewis structure
representation of a molecule where valence electrons are shown as dots
Lone pair
electron pairs of valence electrons not shared with another atom
in a covalent bond
Molecule
when two or more non-metal atoms are covalently bonded together
Molecular formula
actual number of atoms in a molecule
Non-polar covalent bond
covalent bond between two atoms of similar electronegativity
Permanent dipole
permanent area of partial positive or partial negative charge
on a molecule
Polar covalent bond
covalent bond between atoms of differing electronegativities
Polar molecule
asymmetrical molecule with a partially positively charged end
and a partially negatively charged end
Polarity
property of having a partial positive and negative charge
Structural formula
shows all the atoms and bonds in a molecule or compound
Unpaired electron
electron in an orbital by itself
Valence shell electron pair repulsion theory (VSEPR)
model used to predict
the different shapes of molecules based on the repulsion between electron pairs
Boiling point
temperature at which a liquid transitions into a gas
Hydrogen bonding
a special type of permanent dipole-dipole attraction between
molecules (not a covalent bond) that results from the attractive force between
a hydrogen atom covalently bonded to a very electronegative atom such as an
N, O, or F atom
Instantaneous dipole
partial positive and negative charge that appears
in an atom/molecule due to the random movement of electrons
Intermolecular forces
forces that attract adjacent molecules to each other
Kinetic energy
the level of movement of a particle, molecule or molecular substance
Melting point
temperature at which a substance changes state from solid to liquid
Non-conductivity
the inability of a molecule to conduct electricity
Molecular substance
substance with two or more non-metal atoms joined
by covalent bonds
Permanent dipole-dipole attraction
electrostatic force of attraction between
the permanent dipoles of adjacent polar molecules
Temporary dipole-dipole attraction (dispersion force)
electrostatic force of attraction
between two instantaneous dipoles of adjacent molecules
Allotrope
one of the different physical forms an element can take due to different
structural arrangements of atoms
Covalent layer lattice
atoms covalently bonded together in a two-dimensional
arrangement to form layers, held together by weak dispersion forces
Covalent network lattice
regular three-dimensional arrangement of atoms covalently
bonded together extending outwards
Lattice
a series of atoms arranged in a regular pattern
Macromolecule
molecule containing a very large number of atoms such as a giant
atomic covalent lattice of diamond or graphite
Tetravalent
describes an atom with four electrons in its valence shell