Group 13: The Boron Family

Group 13 Atomic Properties

All elements except Thallium (Tl) have a +3 oxidation state, and the +1 state becomes more common down the group.

Atomic Size Comparison

Group 13 elements have a smaller atomic size than Group 2.

Electronegativity (EN)

Group 13 elements have a higher electronegativity than Group 2.

Ionization Energy (IE) Trends

Group 13 elements have lower ionization energy than Group 2 because it is easier to remove an electron from the higher energy p sublevel.

Trends in Group Properties

Atomic size, EN, and IE do not change as expected down the group due to intervening transition and inner transition elements.

Bonding Types in Group 13

Bonding changes from network covalent in Boron to metallic in other elements of the group.

Boron Physical Properties

Boron has a higher melting point than the other elements of group 13.

Boiling Points Trend in Group 13

Boiling points decrease down the group.

Density Trends in Group 13

Densities increase down the group.

Boron Characteristics

Boron is a metalloid that forms electron deficient compounds and is less reactive at room temperature, forming only covalent bonds.

Aluminum Abundance

Aluminum is the most abundant metal in the Earth's crust and does not occur in its elemental form in nature.

Hall-Heroult Process

An industrial process used to obtain aluminum through electrolyzing a molten salt bath of Cryolite to alumina.

Amphoteric Nature of Aluminum Oxides

Aluminum oxides can react as both acids and bases, termed amphoteric.

Oxides of Group 13 Elements

All members react with O2 to form oxides, and oxide acidity decreases down the group.

Basicity of Boron Oxide

Boron oxide (B2O3) reacts with NaOH to form sodium borate (Na3BO3) and water.

Behavior of Aluminum Oxide

Aluminum oxide (Al2O3) reacts with both bases and acids, showing amphoteric behavior.

Thallium Oxides

Indium (In) and Thallium (Tl) oxides are basic and react only with acids.