Acids and Bases - introduction
1. The Bronsted-Lowry theory involves the transfer of
solution.
2. A(n)
acceptor.
or hydrogen ions in an
is a molecule or compound that acts as a proton donor. A(n)
acts as a proton
3. In the reaction HCl + H2O < -- > H3O+ + ClThe
acts as the acid because it donates a proton to the
base because it accepts the H+.
4. The H3O+ion is called the hydronium ion, or the
. The
acts as a
ion and it shows a water bonded to an H+.
5. If you split the equation above into two half equations, you can see the acid + conjugate base pair, and the base +
conjugate acid
HCl
Cl-
< -- >
+
H+
H2O + H+ < -- >
Acid
H3O+
Base
An acid base reaction always involves at least two conjugate pairs that differ by an H+.
6. Now look at this reaction:
NH3
+
H2O
< - - > NH4+
+
OH-
Identify the acid (a), the base (b), the conjugate acid (ca) and the conjugate base (cb) (no clues for this question)
7. HCl +
NH3
+
H3O+
+
Cl-
< - - > NH4+
+
OH-
H2O < -- >
H2O
Look at the two equations above: what do you notice about how the water is behaving?
.
The term for this is
. It can either accept or donate a proton.
Many amino acids are amphiprotic: H2N – CH2 – COOH Circle the acidic part and the underline basic part
8. An
species is one that can act as an acid and a base. All amphiprotic species are
amphoteric, but not all amphoteric species are amphiprotic.
9. A Lewis acid is a species that is able to accept an electron pair from a Lewis base to form a
bond where only one species donates both electrons to form a covalent bond).
10. A Lewis base is able to
Mg(OH)2 < - - > Mg2+ + OHThe Mg2+ acts as a
form [Mg(H2O)]2+
a pair of electrons to form a dative bond.
(the OH- is a Bronsted-Lowry base as it can accept a proton)
as it coordinates with a lone pair on an H2O molecule in a dative bond to
(a
conjugate base
aqueous
dative bond
HCl
H2O
Lewis acid
base
protons
H2O
donate
oxonium
amphoteric
amphiprotic
conjugate acid
acid