Advanced Topic 645 of 1102 Inorganic Chemistry
Carbides
Binary compounds of carbon with less electronegative elements, ionic, covalent or interstitial.
In-depth explanation of Carbides
Carbides are binary compounds of carbon with a less electronegative element, classified as ionic, covalent or interstitial. Ionic carbides of the most electropositive metals, such as CaC2 and Al4C3, contain carbide anions and hydrolyse in water to give hydrocarbons. Covalent carbides such as SiC and B4C are extremely hard and refractory, which makes them useful as abrasives. Interstitial carbides, such as tungsten carbide, WC, and the cementite Fe3C in steel, have carbon atoms in the gaps of a metal lattice and remain metallic in conductivity.
Going deeper: Carbides
Key ideas: Three types: ionic or saltlike (CaC2 with C2 2-, Al4C3 with C4-), covalent (SiC, B4C, very hard, used as abrasives), and interstitial metallic (WC, TiC, Fe3C, hard and conductive). Hydrolysis: CaC2 + 2H2O gives C2H2 + Ca(OH)2 and Al4C3 + 12H2O gives 3CH4 + 4Al(OH)3. Cementite Fe3C controls steel hardness.
Common mistakes and connections: Students assume all carbides release acetylene on hydrolysis; only acetylides do, while Al4C3 gives methane and Mg2C3 gives propyne. SiC is not ionic, it has a diamond-like network. Carbon-rich type distinction rests on the anion present. Links to steel, hardness of materials and organic acetylene synthesis.
Visualization of Carbides
Acetylene, HC≡CH, is released when ionic calcium carbide CaC2 (containing the C2 2- ion) reacts with water. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Calcium carbide reacts with water to produce acetylene: CaC2 + 2H2O giving Ca(OH)2 + C2H2.
Frequently asked questions about Carbides
What is Carbides?
Binary compounds of carbon with less electronegative elements, ionic, covalent or interstitial.
Is Carbides a beginner, intermediate or advanced topic?
Carbides is a advanced topic in Inorganic Chemistry. It builds on beginner and intermediate topics, so review those first if needed.
What should I learn before Carbides?
Study these earlier topics in Inorganic Chemistry first: Silicones, Glass, Carbon Oxides.
What comes after Carbides?
The next topics in Inorganic Chemistry are Nitrogen Family and Ammonia.
Can I practise Carbides with quizzes?
Yes. The interactive lesson includes a self-check question on Carbides, and the Inorganic Chemistry quiz draws on every topic in this area.
Where Carbides fits in Inorganic Chemistry
Carbides is topic 30 of 113 in Inorganic Chemistry.