Chemistry Reference
In-Depth Information
OH
Arrhenius base
(8.4) A compound that provides
ions
base dissociation constant
(19.2) The equilibrium constant
that controls the extent of ionization of a weak base in
water; symbolized
base strength
(19.1) The tendency for a certain percentage
of molecules of a base to ionize in water; the higher the
base strength, the higher is the percent ionization.
basic anhydride
(8.4) A metal oxide that can react with wa-
ter to form a base.
battery
(17.1) A combination of two or more galvanic cells.
bent molecule
(13.4) See
angular molecule
.
benzene
(20.1) the simplest aromatic hydrocarbon.
beta particle
(21.1) A high-energy electron emitted from a
nucleus in a nuclear reaction; a stream of such particles
is called a beta ray.
binary compound
(5.1) A compound composed of two
elements.
biochemistry
(Chapter 1, Introduction) The branch of
chemistry dealing with living things.
Bohr theory
(4.2) The first theory of the atom to propose
that electrons in atoms were in definite energy levels.
boiling point
(14.2) The temperature at which a liquid
changes to a gas at the prevailing pressure.
boiling-point elevation
(15.6) An increase in the boiling
point of a solvent due to the presence of a solute.
bond
See
covalent bond
and
ionic bond
.
bond order
See
total bond order
.
Boyle's law
(12.2) At constant temperature, the volume of a
given sample of gas is inversely proportional to its
pressure.
Brønsted acid
(19.1) A proton donor.
Brønsted base
(19.1) A proton acceptor.
Brønsted theory
(19.1) A theory of acids and bases that is
broader than the Arrhenius theory in that it does not
limit acids and bases to water solutions and it defines
ions as acids or bases depending on their tendency to
react with water.
buffer solution
(19.4) A solution of a weak acid and its con-
jugate base or a weak base and its conjugate acid, which
resists changes in its acidity even on addition of a mod-
erate quantity of strong acid or strong base.
build-up principle
(4.4) The addition of an electron to the
configuration of an atom of the preceding element on
the periodic table allows determination of the electronic
configuration of an atom of a given element.
buret
(11.3) A piece of laboratory glassware calibrated for
measuring the volume of liquid delivered.
to water.
Arrhenius theory
(8.4) The fundamental theory of acids
and bases. (Contrast with
Brønsted theory
.)
atmosphere
(12.1) A unit equal to 760 torr and abbreviated
atm that is the pressure of the atmosphere on a “normal”
day at sea level; the envelope of air surrounding the
Earth.
atmospheric pressure
(12.1) The pressure of the atmosphere.
atom
(3.2) The smallest particle that retains the characteris-
tic composition of an element.
atom smasher
(21.3) A machine designed to initiate nuclear
reactions.
atomic bomb
(21.3) A nuclear bomb; a bomb in which mat-
ter is converted to energy for destructive purposes.
atomic mass
(3.4, 7.1) The weighted average of the masses
of the naturally occurring isotopes of an element, com-
pared with one twelfth of the mass of a atom.
atomic mass scale
(3.4) A relative scale of masses based on
the mass of being the standard and having a mass
defined as exactly 12 amu.
atomic mass unit
(3.4) A mass equal to one twelfth of the
mass of a atom; abbreviated amu.
atomic number
(3.3) The number of protons in the nucleus
of each atom of an element.
atomic size
(13.1) The size of an atom.
atomic theory
See
Dalton's atomic theory
.
atomic weight
See
atomic mass
.
atomic weight scale
(3.4) Atomic mass scale.
autoionization
(19.3) A reaction of molecules of a single
substance to produce both positive and negative ions;
for example, water molecules react to produce both
and ions.
autooxidation-reduction
See
disproportionation
.
average kinetic energy
(12.10) The total kinetic energy of
all the molecules of a sample, divided by the number of
molecules; the average kinetic energy is dependent on
temperature only.
Avogadro's number
(7.3) which is the num-
ber of atoms in exactly 12 g of (as well as the
number of atomic mass units in exactly 1 g).
K
b
.
C
6
H
6
,
12
C
12
C
12
C
H
3
O
OH
6.02
10
23
,
12
C
12
C
balanced equation
(8.1) A written representation of a chem-
ical reaction in which formulas of the reactants and
products appear on two sides of an arrow, with coeffi-
cients to make the numbers of atoms of each element
the same on both sides.
barometer
(12.1) An instrument for measuring the pressure
of a gas, especially the atmosphere.
barometric pressure
(12.1) The pressure of the atmosphere.
base
(6.3, 8.4) A compound that provides
carbohydrate
(20.5) A compound containing carbon plus
hydrogen and oxygen in a mole ratio of
2:1;
the general
formula is
carbonate
(8.4) An ionic compound containing the
ion.
catalyst
(8.3, 18.1) A material that affects the speed of a
chemical reaction without any permanent change in its
own composition.
C
x
H
2
y
O
y
.
OH
2
3
ions to water
CO
solutions. (See also
Brønsted base
.)
base
(2.2) The number that is raised to a power and multi-
plied by a coefficient in an exponential number; for ex-
ample, the 10 in 1.5
10
2
.
