Chemistry Reference
In-Depth Information
4.50
See the accompanying figures. The numbers of unpaired elec-
trons are
(a)
One
4.77 (a)
One
(b)
Five
(c)
Five
4.84
The atom with the most unpaired electrons will be drawn into
the magnetic field the most.
(a)
Mn (has 5 unpaired electrons)
(b)
Cu (has 1 unpaired electron)
(c)
V (has 3 unpaired electrons)
(d)
Ti (has 2 unpaired electrons)
4.86
The actual configuration has six unpaired electrons, and
chromium is drawn into a magnetic field more than would be
expected from the
(b)
Two
(c)
Zero
(d)
Two
_
↑
_
↑
↑↓
_
↑
_
↑
__
__
2
p
2
p
↑↓
↑↓
__
__
2
s
2
s
↑↓
↑↓
__
__
1
s
1
s
Boron
Oxygen
4
s
2
3
d
4
configuration, with four unpaired
_
↑
_
↑
__
electrons.
3
p
↑↓
__
5 Chemical Bonding
5.1
3
s
↑↓
↑↓
↑↓
↑↓
↑↓
↑↓
__
__
__
__
__
__
(a)
The valence shell is the outermost shell of an uncom-
bined atom. If all the valence electrons have been re-
moved, the outermost shell of the resulting positive ion
will be the shell just below the valence shell.
(b)
Diatomic
means two atoms per molecule;
binary
means
two elements per compound.
2
p
2
p
↑↓
↑↓
__
__
2
s
2
s
↑↓
↑↓
__
__
1
s
1
s
Neon Silicon
4.51 (e)
(The 15 electrons lie in the lowest energy orbitals possi-
ble, with the three electrons in the 3
p
subshell in separate
orbitals with parallel spins.)
4.55 (a)
Two
(b)
Six
(c)
Ten
(d)
Fourteen
In each case, the width of the block in the periodic table gives
the number of electrons. For example, the
s
block is two
groups wide.
4.56 (a)
Two each
(b)
Ten each
(c)
Eighteen each
4.58 (a)
Be
(b)
Mg
(c)
Ca
(d)
Sr
4.60 (a)
Ge
(b)
Mn
(c)
N
(d)
Br
(e)
Fe
4.62 (a)
Tl [Xe]
(b)
La [Xe]
(c)
Gd [Xe]
4.67 (a)
Mn
(b)
Te
(c)
Bi
(d)
Rb
(e)
Br
(f )
Lr
4.68
The differences corresponding to the possible transitions are
as follows:
From 5 to 4:
From 5 to 3:
From 5 to 2:
From 4 to 3:
From 4 to 2:
From 3 to 2:
4.71
No.
Every
element with an atomic number 4 or greater has
this
inner
configuration.
4.75 (a)
A1
p
subshell does not exist.
(b)
There is only one 1
s
electron.
(c)
The 2
s
, 3
s
, 3
p
, etc. subshells are missing.
(d)
The 2
p
subshell is not filled.
(e)
There are too many electrons in the 4
f
subshell.
(f )
There are too many electrons in the 3
d
subshell.
(g)
There are too many electrons in the 2
s
subshell.
(h)
There is no 2
d
subshell.
(i)
5.2
Diatomic molecules:
uncombined elements
Charges on ions:
ionic compounds
5.3
(a)
It has only 1 electron to lose.
(b)
The first shell can hold only 1 additional electron.
5.4
Ionic:
(b)
Covalent:
MgCl
2
(a)
Cl
2
and
(c)
SCl
2
5.5
(a)
Hydrogen is a group IA element, but it is not a metal.
(b)
Because hydrogen can form
H
ions, only the first state-
ment is correct.
(c)
No. All group IIA elements are metals.
5.6
The first is an ionic chloride of cobalt; the second contains
carbon and oxygen as well as chlorine, all covalently bonded.
1
s
2
2
s
2
1
s
2
2
s
2
2
p
6
3
s
2
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
Zn
2
F
5.7
(a)
ZnBr
2
(b)
and
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
3
d
10
4
p
6
5
s
2
Fe
2
O
2
(c)
SnO
(d)
and
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
3
d
10
4
p
2
5.8
Eight, five from the outermost shell of nitrogen and three ex-
tra transferred from some cation(s).
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
3
d
5
1
s
2
2
s
2
2
p
3
5.9
(a) (b) (c)
0
(d) (e)
The charge on the zinc ion in each of its compounds is
(equal to its group number). In the free element, as in all free
elements, the charge on the atom is zero.
2
2
2
2
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
3
d
10
4
p
5
2
1
s
2
2
s
2
2
p
6
3
s
2
3
p
6
4
s
2
3
d
6
6
s
2
5
d
10
4
f
14
6
p
1
6
s
2
5
d
1
5.10
(a)
0
(b)
(c)
(equal to the atomic number)
Note the great difference in the meaning of the questions
with only a slight difference in the wording.
2
6
s
2
5
d
1
4
f
7
20
5.11
(a)
The alkali metals, the alkaline earth metals, the group IIIB
metals, silver, zinc, cadmium, and aluminum
(b)
The group IA and group IB metals
4.898
10
20
J
1.549
10
19
J
4.574
10
19
J
NH
4
5.12
NH
3
and
1.059
10
19
J
5.13
(a)
(UO
2
)
3
(AsO
4
)
2
(b)
(MO
y
)
3
(XO
z
)
2
4.084
10
19
J
(c)
(AX
y
)
3
(BZ
z
)
2
(d)
The charges on the ions must
be balanced no matter
what
the identity of each ion.
3.025
10
19
J
5.14
(a)
Yes, it has the electronic structure of He.
(b)
No; it has no electrons. (This ion is not a stable species,
but chemists often use the symbol
H
H
3
O
.)
to represent
5.15
The first is a compound, and the second is an ion—part of a
compound.
5.16
CdS in all cases. Note the different ways in which the same
problem may be presented.
5.17
Atoms of the main group elements except for the noble gases
have valence electrons equal in number to their (classical)
periodic group numbers.
The 3
d
subshell, not the 4
d
subshell, follows the 4
s
sub-
shell.
