Boiling block metals

Like some other d-block metals, such as nickel, iron can form compounds in which its oxidation number is zero. For example, when iron is heated in carbon monoxide, it reacts to form iron pentacarbonyl, Fe(CO)5, a yellow molecular liquid that boils at 103°C. 

Table 4.18 Melting and boiling points of s-block metals... 

The d-block metals (except mercury and cadmium) typically have relatively high melting and boiling points (Figure 13.6) compared to the non-d-block metals.This is a consequence of strong metallic bonding (Chapter 4) because the first-row d-block metals have valence electrons from the 3d and 4d sub-levels. 

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