Understanding Allotropes of Carbon

This video tutorial explores the structure and properties of two carbon allotropes: diamond and graphite. It explains that allotropes are different structural forms of the same element in the same physical state. Diamond is a giant covalent structure where each carbon atom is bonded to four others, making it very strong with a high melting point but non-conductive. Graphite, on the other hand, has carbon atoms bonded to three others, forming layers that can slide over each other, making it softer but conductive due to delocalized electrons. The video also briefly introduces graphene and fullerenes, which will be covered in the next video.

What are allotropes?

• Different compounds in the same physical state

• Different structural forms of the same element in the same physical state

• Different structural forms of different elements in the same physical state

• Different elements in the same physical state

How many covalent bonds does each carbon atom form in diamond?

• Five

• Four

• Three

• Two

Why doesn't diamond conduct electricity?

• It has no free electrons or ions

• It has free electrons

• It has a metallic structure

• It has free ions

How many covalent bonds does each carbon atom form in graphite?

• Four

• Three

• Two

• Five

What allows graphite to conduct electricity?

• Presence of free protons

• Presence of free ions

• Presence of metallic bonds

• Presence of delocalized electrons

What is the arrangement of carbon atoms in graphite?

• Tetrahedral

• Hexagonal sheets

• Cubic

• Linear chains

What is the main difference in the bonding of carbon atoms between diamond and graphite?

• Diamond has metallic bonds, graphite has ionic bonds

• Diamond has four covalent bonds per carbon atom, graphite has three

• Diamond has ionic bonds, graphite has covalent bonds

• Diamond has three covalent bonds per carbon atom, graphite has four

Why is graphite softer than diamond?

• Graphite has weaker covalent bonds

• Graphite layers are held together weakly

• Graphite has a different chemical composition

• Graphite has a lower melting point

What is a single layer of graphite called?

• Carbon nanotube

• Graphite

• Graphene

• Fullerene

What will be explored in the next video?

• The melting point of carbon

• Graphene and fullerenes

• The properties of graphite

• The structure of diamond