Terms
Acid
-
A substance that has the potential to donate a proton or accept an electron
pair.
Acidic
-
Having a pH less than 7.
Base
-
A substance that can accept a proton, release OH-, or donate an
electron pair.
Basic
-
A solution with a pH greater than 7.
Buffer
-
A solution composed of an acid and its conjugate base that serves to
moderate the pH of the
solution.
Conjugate Acid
-
A molecule that can be described as a base that has gained one proton.
Conjugate Base
-
A molecule that can be described as an acid that has lost one proton.
Endpoint
-
The volume or amount of acid or base added to a solution to neutralize the
unknown solution during a
titration. When using an indicator, the endpoint occurs when
enough titrant has been
added to change the color of the indicator.
Equivalence Point
-
The volume of titrant and pH at which the amount of acid equals the
amount
of base present in the original solution, or the amount of base equals the
amount of acid present in the original solution.
Indicator
-
A molecule whose conjugate acid or conjugate base has a different color.
An indicator is used to mark a certain pH level.
pH
-
A measure of the hydrogen ion concentration, it is equal to - log
[H+].
pKa
-
A measure of the strength of an acid, it is equal to - log
Ka, where Ka is the acid dissociation
constant
in water.
pKb
-
A measure of the strength of a base, it is equal to - log
Kb, where Kb is the base dissociation
constant
in water.
Strong Acid
-
An acid with a pKa less than zero. Strong acids
completely
dissociate in water.
Strong Base
-
A base with a pKb less than zero. Strong bases
completely
dissociate in water.
Titrant
-
The acid or base of known amount and concentration that is added to the
unknown solution during an
acid-base titration.
Titration
-
An experiment where an unknown concentration of acid or base is
neutralized with a
known volume and
concentration of acid or base to determine the concentration of the unknown.
Titration Curve
-
A plot of solution pH versus titrant volume during a titration.
Weak Acid
-
An acid with a pKa greater than zero. Weak acids do
not
completely dissociate in
water.
Weak Base
-
A base with a pKb greater than zero. Weak bases do
not
completely dissociate in
water.
