Beginner Topic 730 of 1102 Organic Chemistry
Tetravalency of Carbon
Carbon forms four bonds, allowing chains, rings and enormous molecular diversity.
In-depth explanation of Tetravalency of Carbon
Carbon has four valence electrons and forms four covalent bonds, which is why it is described as tetravalent. Its hybridization determines geometry: sp3 carbon is tetrahedral with bond angles near 109.5 degrees, sp2 carbon is trigonal planar with angles near 120 degrees, and sp carbon is linear with angles of 180 degrees. Carbon has a moderate electronegativity of about 2.5, so its bonds to hydrogen and to other carbons are strong and only weakly polar. This combination of strength, four bonding sites and mild polarity makes carbon the backbone of stable, diverse molecules.
Going deeper: Tetravalency of Carbon
Key ideas: Count bonds, not electrons: every neutral carbon has four bonds in total, and a double bond counts as two. Use hybridization to get shape: four sigma bonds is sp3 (25 percent s character), a double bond sp2 (33 percent), a triple bond sp (50 percent). More s character means shorter, stronger bonds and higher electronegativity: C-C 154 pm, C=C 134 pm, C-C triple 120 pm.
Common mistakes and connections: A common slip is drawing a carbon with five bonds, or forgetting implicit hydrogens in skeletal structures. Students also think carbon can only form four single bonds, missing that carbocations (three bonds) and carbanions (three bonds plus a lone pair) are legitimate intermediates. Connects to hybridization, VSEPR and isomerism.
Visualization of Tetravalency of Carbon
Carbon forms four single bonds directed to the corners of a tetrahedron with 109.5 degree angles, because its four valence electrons pair up in sp3 hybrids. The interactive lesson shows this as a live animation or chart.
Worked example and use case
In methane, CH4, carbon uses all four valence electrons to bond with four hydrogens in a tetrahedral arrangement.
Frequently asked questions about Tetravalency of Carbon
What is Tetravalency of Carbon?
Carbon forms four bonds, allowing chains, rings and enormous molecular diversity.
Is Tetravalency of Carbon a beginner, intermediate or advanced topic?
Tetravalency of Carbon is a beginner topic in Organic Chemistry. It needs no earlier chemistry lessons and is a good starting point.
What should I learn before Tetravalency of Carbon?
Study these earlier topics in Organic Chemistry first: Organic Chemistry.
What comes after Tetravalency of Carbon?
The next topics in Organic Chemistry are Catenation and Functional Groups.
Can I practise Tetravalency of Carbon with quizzes?
Yes. The interactive lesson includes a self-check question on Tetravalency of Carbon, and the Organic Chemistry quiz draws on every topic in this area.
Where Tetravalency of Carbon fits in Organic Chemistry
Tetravalency of Carbon is topic 2 of 148 in Organic Chemistry.