Section 1.1 Section 1.2 Section 1.3 - The Student Room

SECTION 3
c
d
e
f
Mg
Ca
Ca
Na
2+
2+
2+
+
X
O
X
XX
XX
Cl
X
XX
X
S
X
XX
Na
X
X
X
X
X
X
+
2–
–
2–
XX
Cl
X
XX
X
S
X
XX
X
X
X
X
–
2–
5 a In a normal covalent bond, each atom supplies a single
electron to make up the pair of electrons involved in
the bond. In a dative covalent bond one atom supplies
both electrons.
b
+
H
6
H
H
X
N
X
X
H
X
O
X
H
H
H
+
H
X
N
X
H
X
H
g
h
Na
Al
+
3+
X
X
Na
F
X
XX
+
X
X
–
Na
X
X
F
X
XX
+
X
X
–
X
X
N
X
X
X
X
X
F
X
XX
3–
X
X
–
7
H
H
X
X
N
X
H
X
X
XX
X
X F
X
X
X XX
B
X
F
X
X
X XX
X
X F
X
X
XX
4 a
b
c
d
e
f
g
X
X
H
H
H
X
X
XX
Cl X Cl
XX
XX
Cl
X
XX
X
H
X
C
X
X
X
X
H
XX
S
X X
XX
XX
X
Br
XX
XX
X
X Br
X
Al
XX X
X X
X Cl
XX X
H
H
X
X
Si
H
H
XX
X X
X Cl X
X X
X Cl X
XX
C
X
X
X
X
X
X
XX
X
Br
XX
X
X
XX
X X
Cl X
XX
C
X
X
H
H
8 Chlorine has a stronger electron pulling power. Thus in a
covalent bond between carbon and chlorine, the
electron pair forming the bond is more strongly attracted
by the chlorine atom than by the carbon atom.
9 a H—F b N∫N
d+ d– non-polar
c H—Cl
d Cl—F
d+ d– d+ d–
e H—I
f S=C=S
d+ d– non-polar
10 a Three
b The delocalised electrons form a pool of electrons
which are free to move around the positive ions in the
metal. When a potential difference is applied across
the metal, electrons move towards the positive
terminal, ie a current flows.
11 a Metallic b Covalent c Covalent
d Ionic e Ionic f Covalent
Silicon tetrafluoride contains polar covalent bonds.
12 a NaCl
b MgCl 2
c FeCl 3
d Al 2
O 3
e NH 4
Cl
f NaOH
g K 2
CO 3
h MgSO 4
h
i
H
H
X
X
C
H
X
X
X
C
H
X
X
X
O
X
X C H
X
X
X
H
13 a NH 3
b H 2
S
c CO 2
d HCl
e CO
f SO 2
g N 2
O
h SO 3
165