AQA Unit 2 Chemistry

Question 1

What are the three types of bonding in chemistry?

Answer 1

Metallic, Ionic and Covalent

Question 2

What is an ion?

Answer 2

an atom which has lost or gained an electron

Question 3

If something has gained electrons, what charge will it have?

Answer 3

Negative

Question 4

If something has lost electrons, what charge will it have?

Answer 4

Positive

Question 5

Why do atoms transfer electrons in ionic bonding?

Answer 5

So that they can have full outer shells

Question 6

What is the name for a substance made of billions of oppositely charged ions joined together?

Answer 6

Giant ionic lattice

Question 7

Explain why ionic substances have high melting points.

Answer 7

Strong electrostatic attractions between oppositely charged ions are hard to break

Question 8

Explain why ionic compounds conduct electricity in solution

Answer 8

Because the ions are free to move

Question 9

Complete the sentence: In covalent bonds, electrons are _______________________

Answer 9

Shared

Question 10

What is the name given to the structure of diamond, graphite and silicon dioxide?

Answer 10

Giant covalent

Question 11

Explain why diamond has a high melting point

Answer 11

Giant structure, Strong covalent bonds between the atoms, requires a lot of energy to break

Question 12

Explain why graphite conducts electricity

Answer 12

Has delocalised electrons between the layers that can move through the graphite

Question 13

What type of substance are methane and water?

Answer 13

Simple molecular (or simple molecules)

Question 14

Explain why methane has a low melting point

Answer 14

It is a simple molecular substance with weak forces between the molecules (which are easy to break)

Question 15

Explain why metals can conduct electricity

Answer 15

Delocalised electrons are free to carry charge