Chapter 5: The Periodic Table

Groups

Vertical arrangement of elements in the periodic table with similar chemical properties.

Periods

Horizontal arrangement of elements in the periodic table.

Alkali metals

Elements in Group 1 of the periodic table.

Alkaline-earth metals

Elements in Group 2 of the periodic table.

Transition elements

Metals in the d-block with typical metallic properties.

P-block

Elements in Groups 13-18 (excluding helium).

Main-group elements

P-block elements combined with s-block elements.

Halogens

Elements in Group 17, most reactive nonmetals.

Metalloids

Elements between nonmetals and metals in the p-block.

F-block

Elements wedged between Groups 3 and 4 in the sixth and seventh periods.

Lanthanides

First row of the f-block, shiny metals similar in reactivity to Group 2 alkaline metals.

Actinides

Second row of the f-block, all radioactive elements.

Atomic Radii

Size of an atom.

Electron Affinity

Atom's tendency to gain an electron.

Ionic Radii

Size of an atom after gaining or losing electrons.

Electronegativity

Atom's ability to attract electrons.

Ionization energy

Energy required to remove an electron from an atom.

Valence electrons

Electrons available for chemical bonding.

Periodic Law

Properties of elements are periodic functions of their atomic numbers.