Modern inorganic chemistry

360 THE TRANSITION ELEMENTS

copper shows many of the characteristic properties of transition

elements, and zinc is, as it were, half way between a transition and a

main group element. It is therefore convenient to include copper

and zinc in the first transition series (Table 13.2}

Table 13.2

PHYSICAL PROPERTIES OF THE FIRST TRANSITION SERIES ELEMENTS

Element Sc Ti Cr Mn Fe Co Ni Cu

7.1 7.4 7.9

70

Zn

Density

(gem"^3 ) 3.2 4.5 6.0

Hardness*

(kg mm"^2 ) — 200 — 100 300

(Brinell scale)

m.p.(K) 1673 1950 2190 2176 1517 1812 1768 1728 1356 693

b.p.(K) 2750 3550 3650 2915 2314 3160 3150 3110 2855 1181

8.7 8.9 8.9 7.1

48 70-80 30-40 30

* These values are very dependent on the purity and heat-treatment of the metal.

It is immediately obvious that the transition metals are more

dense, harder, and have higher melting points and boiling points

than the main group metals (for example, the metals of Group II,

3500

3000

2500
a.
JD

2000

1500

(^110021) 22 23 24 25 26 27 28 29 30
Sc Ti V Cr Mn Fe Co Ni Cu Zn
Atomic number
Figure 13.1. Graph oj b.p, against atomic number jor thejirst transition series