Physical Properties Of Covalent And Ionic Structures

Question 1

What method is used to show bonding?

Answer 1

X-ray crystallography

Question 2

Give 4 examples of allotropes of carbon.

Answer 2

Diamond, Graphite, Graphene and Fullerene.

Question 3

What are some examples of Covalent Network Solids?

Answer 3

Graphite, diamond and graphene. Large structures that are held together by covalent bonds.

Question 4

What is the fancy name for the shape of a fullerene?

Answer 4

Truncated Icosahedron

Question 5

Graphite.

Answer 5

Layers of covalently bonded hexagonal rings. Carbon bonded to 3 other carbons which makes it conduct electricity because the sea of delocalised electrons are able to move around. Weak intermolecular forces. Used in pencils.

Question 6

Diamond.

Answer 6

Each carbon is bonded to 4 others in a tetrahedral arrangement. No conductivity. Used in saws, polishing tools and dental equipment because it is so hard.

Question 7

Graphene.

Answer 7

Only 1 atom thick and strongest material. Excellent conductor. Transparent and becomes a nanotube when rolled.

Question 8

Fullerene.

Answer 8

Truncated icosahedron. Does not conduct electricity despite delocalised electrons. They cannot transfer between. Good gene/drug carriers.

Question 9

Silicon Dioxide.

Answer 9

Covalent network solid. Does not conduct electricity in solid since no delocalised electrons. Does conduct in molten state. It is present in quartz.

Question 10

NaCl and other ionic compounds.

Answer 10

Giant ionic lattice. High melting and boiling points. When molten they conduct electricity, when solid they do not.