Final answer:
Diamonds are highly refractive crystalline allotropes of carbon. They have a tetrahedral structure with strong carbon-carbon single bonds, making them hard and giving them high melting points. The high index of refraction causes light to enter the diamond at different angles and exit only at a few points, creating the sparkling effect.
Step-by-step explanation:
Diamonds are highly refractive crystalline allotropes of carbon. Diamonds are highly refractive crystalline allotropes of carbon. They have a tetrahedral structure with strong carbon-carbon single bonds, making them hard and giving them high melting points. The high index of refraction causes light to enter the diamond at different angles and exit only at a few points, creating the sparkling effect.
Each carbon atom in a diamond forms four single bonds with four other atoms arranged in a tetrahedral structure, resulting in a giant molecule. The carbon-carbon single bonds are very strong and extend throughout the crystal, making diamonds hard and giving them high melting points. Diamonds also have a high index of refraction, which causes light to enter the diamond at different angles and exit only at a few points, resulting in the sparkling effect.