Modern inorganic chemistry

Group V

(Nitrogen, phosphorus, arsenic, antimony, bismuth)

Table 9.1 below gives some of the physical properties of Group V
elements. The data in Table 9.1 clearly indicate the increase in
electropositive character of the elements from nitrogen to bismuth.
Nitrogen is a gas consisting entirely of diatomic molecules but the
other elements are normally solids. From phosphorus to bismuth
the elements show an increasingly metallic appearance, and arsenic,
antimony and bismuth are electrical conductors. Their chemical
behaviour is in agreement with this, the hydrides MH 3 , for example,
decreasing in stability. Arsenic, antimony and bismuth are all
capable of forming tripositive cationic species in solution. The
oxides become increasingly basic and bismuth(III) hydroxide.

Table 9.1

SELECTED PROPERTIES OF THE ELEMENTS

Element

N

P

As

Sb

Bi

* covalent

t white P.

Atomic Outer

number electrons

1 2s^2 2p^3

15 3s^2 3p^3

33 3^^10 4s^2 4p^3

51 4d^10 5s^2 5p^3

83 5dl()6s^2 6p^3

radius.

Atomic

radius

(nm)

0.070*

0.110*

0.125

0,145

0.170

m.p.

(K)

63

317f

1090t

903

545

b.p.

(K)

77

554t

sublimes

1910

1832

1st

ionisation

energv

(kJ mor J)

1403

1012

947

834

703

Electro-

negativity

(Pauling)

3.0

2.1

2.0

1.9

1.9

t under pressure.

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