Electronic Configurations and Types of Elements: s-, p-, d-, f-Blocks

Fig. 3.3 draws the periodic table as four separate block panels, one per type of orbital being filled — exactly how the book prints it:

• s-BLOCK (groups 1–2): the alkali and alkaline earth metals, rows $2s$ to $7s$ (Li/Be down to Fr/Ra). Hydrogen sits in its own detached $1s$ cell — it belongs to no block-panel, reflecting its unique position.
• d-BLOCK (groups 3–12): the four transition series, rows $3d$ (Sc–Zn) to $6d$ (Ac–Cn). All metals.
• p-BLOCK (groups 13–18): rows $2p$ to $7p$, with helium placed at the top of group 18 despite its $1s^2$ configuration.
• f-BLOCK: the lanthanoids ($4f$, Ce–Lu) and actinoids ($5f$, Th–Lr) as two separate strips.

Overlaid on the block structure is the figure's second classification, by colour: metals, non-metals and metalloids. The metalloid cells in the figure are Si, Ge, As, Sb, Te, Po and At — the staircase zone between metals and non-metals in the p-block. (The chapter text's own list in Section 3.6.5 names Si, Ge, As, Sb and Te; the figure additionally shades Po and At. Boron is coloured as a non-metal in the figure.) The non-metals cluster in the upper right of the p-block — H, C, N, O, F, P, S, Cl, Se, Br, I — and the noble gases (He–Og) carry their own shade. Everything to the left and below — the entire s, d and f blocks plus Al, Ga, In, Sn, Tl, Pb, Bi and the $7p$ metals — is metallic.