S-block

Groups 1A (alkali metals) and 2A (alkaline earth metals) of the periodic table, Hydrogen, and helium make up the S-block (for sharp) elements. These elements have noble gas structures.

An s orbital can hold a maximum of 2 electrons.

Other Blocks:

• d-block
• f-block
• g-block
• p-block

See Electron shell, Orbitals