Beginner Topic 633 of 1102 Inorganic Chemistry
Boron Family
Group 13 elements have three valence electrons, from nonmetallic boron to metallic aluminium.
In-depth explanation of Boron Family
Group 13 comprises boron, aluminium, gallium, indium and thallium, with three valence electrons in the ns2 np1 configuration. Boron is a metalloid that forms mainly covalent compounds, while aluminium and the heavier elements are metals that tend to form M3+ ions. Boron is electron deficient in many compounds, so its trihalides are strong Lewis acids. Down the group the +1 oxidation state becomes more stable because of the inert pair effect, in which the two s electrons resist bonding. The group therefore shifts from nonmetallic at the top to metallic at the bottom.
Going deeper: Boron Family
Key ideas: Group 13 ns2 np1: B, Al, Ga, In, Tl. Boron is a metalloid with strong covalent bonding and forms electron-deficient compounds like BF3 (Lewis acid, incomplete octet). Al is a metal and amphoteric. The inert pair effect makes +1 more stable for Tl, so Tl3+ is oxidizing. Ionization energy is irregular (Ga higher than Al) due to d-block contraction.
Common mistakes and connections: Students often expect smooth trends in size and ionization energy, but Ga is nearly the same size as Al. BF3 is a better Lewis acid than BCl3 in simple terms, yet experimentally BCl3 is stronger since F back-donation into the empty p orbital is greater for fluorine. Links to inert pair effect, boranes and borax.
Visualization of Boron Family
Electronegativity from B to Al: boron (2.0) is a covalent metalloid and aluminium (1.6) is a metal, showing the shift down Group 13. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Thallium(I) compounds are more common than thallium(III) compounds because of the inert pair effect.
Frequently asked questions about Boron Family
What is Boron Family?
Group 13 elements have three valence electrons, from nonmetallic boron to metallic aluminium.
Is Boron Family a beginner, intermediate or advanced topic?
Boron Family is a beginner topic in Inorganic Chemistry. It needs no earlier chemistry lessons and is a good starting point.
What should I learn before Boron Family?
Study these earlier topics in Inorganic Chemistry first: Plaster of Paris, Cement, Magnesium Chemistry.
What comes after Boron Family?
The next topics in Inorganic Chemistry are Borax and Boranes.
Can I practise Boron Family with quizzes?
Yes. The interactive lesson includes a self-check question on Boron Family, and the Inorganic Chemistry quiz draws on every topic in this area.
Where Boron Family fits in Inorganic Chemistry
Boron Family is topic 18 of 113 in Inorganic Chemistry.