Structure and bonding

Question 1

How are ionic bonds formed?

Answer 1

Metal atoms donate electrons to non-metal atoms

Question 2

What is the charge on the metal ion?

Answer 2

Metal ions have a positive charge

Question 3

What is the charge on the non-metal ion?

Answer 3

Non-metal ions have a negative charge

Question 4

Describe the structure of the giant ionic lattice and state what holds ionic compounds together

Answer 4

Giant ionic lattice: a regular structure containing massive numbers of particles that continues in all directions throughout the structure

Strong electrostatic forces of attraction hold the ionic compound together

Question 5

Explain why ionic solids have high melting and boiling points

Answer 5

Many electrostatic forces of attraction have to be overcome. A lot of energy has to be used to overcome these forces

Question 6

Do ionic substances conduct electricity? Explain your answer

Answer 6

Solid ionic compounds do not conduct electricity. When molten (melted) or dissolved in water the ions dissociate, can move and carry the charge

Question 7

What is a molecule? Give examples of covalent bonded molecules

Answer 7

A molecule is a particle made from atoms joined together by covalent bonds

Question 8

How is a covalent bond formed?

Answer 8

Non-metals atoms share electrons

Question 9

What are intermolecular forces?

Answer 9

Intermolecular forces are weak forces between molecules

Question 10

Molecules have low melting points, why?

Answer 10

Molecules are not bonded to each other. Only the weak inermolecular forces have to be overcome so little energy is required

Question 11

Do molecules conduct electricity?

Answer 11

Molecules do not conduct electricity as there is no free electrons/ions to carry the charge

Question 12

What is polymer?

Answer 12

A polymer is a long chain molecule made from joining lots of small molecules together

Question 13

What is a thermosoftening polymer?

Answer 13

Thermosoftening polymer has no bonds between polymer chains that softens when heated

Question 14

Name 3 giant covalent structures.

Answer 14

Diamond
Silicone dioxide
Graphite

Question 15

Why does graphite conduct electricity and diamond does not?

Answer 15

Diamond does not have any free electrons or ions so doesn’t conduct electricity.Graphite has free electrons that can move and carry the charge

Question 16

Why do metals conduct electricity?

Answer 16

Metals conduct electricity because the delocalised electrons can move freely and carry the charge

Question 17

Why do metals have high melting and boiling points?

Answer 17

Very strong attraction between the positive metal ions and the negative electrons is hard to overcome and this takes a lot of energy

Question 18

What is an alloy and why is it harder than a pure metal?

Answer 18

An alloy is a mixture of a metal with small amounts of other elements added, usually other metals. Alloys are hard as the layers are distorted and can no longer slide over each other

Question 19

What are nanoparticles and what are they used for?

Answer 19

Nanoparticles are structures between 1 and 100nm in size, typically containing a few hundred atoms, Nanoparticles are used in drug delivery, sun creams, cosmetics, deodorants and electronics

Question 20

Graphene, fullerene and carbon nanotubes are all examples of nanoparticles. Give examples of what each one can be used for

Answer 20

Graphene: Electronics and carbon fibre
Fullerene: Drug delivery, catalyst
Carbon nanotubes: Make items stronger e.g. tennis rackets