Why is Graphite More Stable Than Diamond: Different Structure and Properties

Why is Graphite more stable than Diamond? In the traditional understanding, Diamond can be said the most stable substance. Why do we say Graphite is more stable than Diamond? In this ultimate guide, learn the overall knowledge of these two substances and check their similarity and differences.

What Is Graphite

Before getting to know “Why is Graphite more stable than Diamond”, it is necessary to learn the definition and property of these two substances.

Graphite is a material with a hexagonal crystal structure made up of layered sheets of carbon atoms. In typical settings, it is the most stable form of pure carbon. Graphite is highly electrically and thermally conductive, very soft, and has a low specific gravity. It is also comparatively non-reactive.

High temperatures and pressures cause carbon to be compressed into graphite, which is why graphite is found naturally in igneous and metamorphic rocks. It is also possible to synthesize graphite by heating substances high in carbon, such as coal tar pitch or petroleum coke. At temperatures between 2500 and 3000 degrees Celsius, the carbon-rich material is sufficiently heated to "purify" it of impurities and enable the carbon to form its hexagonal sheets.

Graphite has a variety of uses. Widely, it is utilized to create pencil cores; its layers can be folded over one another. Graphite is mixed with clay and water to form the pencil lid. The harder the pencil nib is, the more clay they add. Furthermore, graphite is incredibly soft and fractures into thin, flexible flakes that readily slide over one another, giving the impression of grease. Moreover, graphite is employed in electrolysis and to create carbon electrodes for dry cells since it conducts electricity. Electricity is passed via an electrolyte during the process of electrolysis.

What Is Diamond

"A pure or nearly pure, tough form of carbon, naturally crystallized in the isometric system" is the definition of a diamond. Because they are exposed to such high temperatures and pressures in the Earth's mantle, minerals that contain carbon will eventually crystallize. This procedure may take a billion years or longer to complete. The magma from deep volcanic eruptions then pushes the diamond toward Earth's surface. Near the Earth's surface, the lava cools into igneous rock after passing via volcanic pipes. A portion of the diamonds are released by the pipes and could be carried further by flowing water.

A diamond will be assigned to a more industrial purpose if it is not of gem quality.  Based on the Moh's mineral hardness scale, they are the hardest naturally occurring material on Earth. Owing to this characteristic, the substance finds application as an abrasive in powder form and is also included in numerous cutting and drilling instruments. Diamonds' ability to conduct heat well makes them important as well. They are employed in a variety of electronic and computer applications, and their potential industrial usefulness may be expanded by their potential use as semiconductors in microchips.

After having a basic understanding of the two substances, let’s figure out “Why is Graphite more stable than Diamond”.

Why Is Graphite More Stable Than Diamond

Graphite and diamond are two mineral forms of carbon. In the mantle, intense heat and pressure combine to make diamonds. The majority of graphite that is found close to the surface of the Earth developed under lower pressures and temperatures in the crust. Despite having nearly identical compositions, diamond and graphite have quite distinct structures.

So why is Graphite more stable than Diamond? In graphite, a single covalent bond connects each carbon atom to three other carbon atoms to form a hexagonal ring that is layered. It is composed of two-dimensional structural layers. Another name for it is a sandwich-like structure. Every carbon atom in graphite is SP to hybridize, and hexagons are stacked in layers. Covalent bonds bind each carbon atom in the layer to three other carbon atoms in the same plane. The forces between two layers of weak wonder walls satisfy the fourth valence of the carbon atom. Within the layer, the C-C bond length is 0.142 nm, and the C-C distance between the two layers is 0.34 nm.

The reason graphite is more stable than diamond lies in its molecular layer structure and relatively weak bonding. Graphite's layered structure allows the molecular layers to slide relatively easily, making it more stable under certain conditions, especially at high temperatures, as it requires more energy to break its weak bonds, which is also evident in its higher melting point compared to diamond.