How could you describe the changes that happen when carbon changes form from graphite diamond
the answer is: it is a chemical change, which could change some of the intensive and extensive properties of the carbon.
I would say that under increased pressure that carbon changes its crystal structure from the planar sheets of graphite to the face centered cubic structure of diamond.
When carbon changes form from graphite to diamond, there are several distinct differences in the structure, properties, and appearance of the two allotropes of carbon. Here's an explanation of the changes that occur:
1. Structure:
Graphite consists of carbon atoms arranged in layers of interconnected hexagonal rings. These layers are loosely held together by weak van der Waals forces, allowing them to slide past each other. On the other hand, diamond has a three-dimensional, tightly-knit network of carbon atoms. Each carbon atom in diamond is bonded to four neighboring carbon atoms, resulting in a strong covalent network throughout the crystal lattice.
2. Hardness:
Graphite is relatively soft and has a slippery texture due to the weak interlayer bonding. It easily leaves marks on paper when used as a pencil "lead." Conversely, diamond is the hardest naturally occurring material. Its rigid covalent network makes it extremely tough and resistant to scratching, giving it exceptional hardness.
3. Optical properties:
Graphite is opaque and has a black or dark gray color. It is also an excellent conductor of electricity due to the presence of free-moving delocalized electrons in its layers. In contrast, diamond is transparent and can have a range of colors. It is a poor conductor of electricity, as all electrons are localized within the strong covalent bonds.
4. Density:
Graphite has a relatively low density, making it lighter than diamond. The loosely bonded layers allow for a higher volume of empty space within the crystal structure. Diamond, being densely packed with carbon atoms, has a higher density.
5. Crystal structure:
Graphite exhibits a layered crystal structure, while diamond has a cubic crystal structure. The graphite layers can easily slide past each other, which contributes to its lubricating properties. Diamond, with its tightly bonded carbon atoms, is rigid and lacks the ability to slide or deform easily.
To summarize, the transformation of carbon from graphite to diamond involves a rearrangement of carbon atoms, resulting in a distinct change in structure, hardness, optical properties, density, and crystal structure.