Covalent network substances

Which of the following materials is an example of a 3-D covalent lattice?

• Copper

• Diamond

• Carbon dioxide

• Potassium chloride

The two types of bonding in graphite are

• Covalent and ionic

• Metallic covalent

• Ionic and metallic

• Covalent and weak intermolecular forces

The term allotropes describes

• Two atoms of the same element with different mass numbers

• Different forms of the same element in which the atoms combine in different ways

• the term for the arrangement/structure of carbon atoms which is formed from combustion of wood or other plant matter

• the process by which a substance goes directly from the solid phase to the gaseous phase, without passing through the liquid phase

Diamond is hard to the presence of:

• Directional intermolecular forces in 3 dimensions

• Directional dipole-dipole forces in 3 dimensions

• Directional hydrogen bonding in 3 dimensions

• Directional covalent bonding in 3 dimensions

What statement is incorrect about graphite

• It conducts electricity

• It can be used as a lubricant

• It is slippery

• It's melting point is 300 C

Silicon carbide, SiC, has a similar structure to diamond. What type of properties would you expect?

• Hard, good electrical conductor, high melting point

• Hard, good electrical conductor, low melting point

• Soft, good electrical conductor, high melting point

• Hard, poor electrical conductor, high melting point

The difference between graphite and graphene is that:

• Graphite consists of numerous layers of carbon atoms whereas graphene is single layer of carbon atoms

• Graphite consists of multiple layers of carbon atoms whereas graphene is a network lattice of carbon atoms

• Graphite consists of one layer of carbon atoms whereas graphene consists of multiple layers of carbon atoms

• Graphite consists a network of carbon atoms whereas graphene consists of multiple layers of carbon atoms

What arrangement do graphene atoms have?

• A hexagonal arrangement

• A cubic volume-centered arrangement

• A face-centered cubic arrangement

How did scientists discover graphene?

• By peeling layers from the flakes of graphite.

• By taking graphite through the complicated chemical reactions.

• By exposing graphite to a high voltage.

Choose all of the properties that are specific to graphene?

• Flexible.

• Fragile

• Transparent

• Soft.

• Conductive