Chapter 3 Covalent Substances Flashcards
allotrope
different forms of the same element in which the atoms combine in different ways
amorphous
a structure that has no consistent arrangement of particles
asymmetrical molecule
a molecule in which the polar bonds are unevenly (or asymmetrically) distributed; the dipoles do not cancel and an overall molecular dipole is created
combustion
a rapid reaction with oxygen accompanied by the release of large amounts of heat; also called burning
covalent bond
the force of attraction formed when one or more pairs of electrons are shared between two nuclei
covalent lattice
a three-dimensional lattice structure formed from covalently bonded non-metal atoms
covalent layer lattice
an arrangement of atoms in a lattice in which there are strong covalent bonds between the atoms that have formed in a layer
covalent network lattice
an arrangement of atoms in which there are strong covalent bonds between the atoms in all three dimensions
diamond
a form of pure carbon that is the hardest naturally occurring substance
diatomic molecule
a molecule formed from two atoms only
dipole
the separation of positive and negative charges in a molecule
dipole-dipole attraction
a form of intermolecular force that occurs between polar molecules where the partially positively charged end of one molecule is attracted to the partially negative charged end of another molecule
dispersion forces
the force of attraction between molecules due to the temporary dipoles induced in the molecules; the temporary dipoles are the result of random fluctuations in the electron density
double covalent bond
a covalent bond in which four electrons (two electron pairs) are shared
electron density
the concentration of electrons that usually refer to the region around an atom or molecule
electron group
a region of negative charge around an atom, which could be either different types of covalent bonds or a non-bonding pair
electronegativity
the ability of an atom to attract electrons in a covalent bond towards itself
graphite
a form of carbon in which the carbon atoms are arranged in layers
hydrogen bond
a type of intermolecular, dipole-dipole force where a hydrogen atom is covalently bonded to a highly electronegative atom such as oxygen, nitrogen or fluorine
instantaneous dipole
intermolecular force
intramolecular bond
Lewis structure
molecular formula
molecule
non-bonding electron
non-polar
octet rule
permanent dipole
polar
polarity
polyatomic molecule
pyramidal
sublimation point
single covalent bond
structural formula
symmetrical molecule
temporary dipole
tetrahedral
trigonal planar
triple covalent bond
valence shell electron pair repulsion theory (VSEPR)
