Mod 2: Bonding And Structure

Question 1

What are the three main types of bonding?

Answer 1

Ionic, covalent and metallic

Question 2

Define ionic bonding

Answer 2

The electrostatic attraction between positive and negative ions

Question 3

Give an example of a ironically bonded substance

Answer 3

NaCl (sodium chloride - salt)

Question 4

Define covalent bonding

Answer 4

Electrostatic attraction between a shared pair of electrons and the nuclei

Question 5

Define metallic bonding

Answer 5

Electrostatic attraction between the positive metal ions and the sea of delocalised electrons

Question 6

Electrons in which shell are represented in a dot and cross diagram?

Answer 6

The outer shell

Question 7

Why do giant ionic lattices conduct electricity when liquid but not solid?

Answer 7

In a solid state the ions are in fixed positions and this cannot move. When they are in a liquid state the ions are mobile and thus can freely carry charge

Question 8

Giant ionic lattices have a high or low melting and boiling point? Explain

Answer 8

They have a high melting and boiling point because a large amount of energy is required to overcome the electrostatic bonds

Question 9

In what type of solvents do ionic lattices dissolve?

Answer 9

Polar solvents e.g water

Question 10

Why are ionic compounds soluble in water?

Answer 10

Water has a polar bond. Hydrogen atoms have + charge and oxygen atoms have a - charge. These charges are able to attract charged ions.

Question 11

What is it called when atoms are bonded by a single pair of shared electrons?

Answer 11

Single bonds

Question 12

How many covalent bonds does carbon form?

Answer 12

4

Question 13

How many covalent bonds does oxygen form?

Answer 13

2

Question 14

What is a lone pair

Answer 14

Electrons in the outer shell that are not involved in the bonding

Question 15

What is formed when atoms share two pairs of electrons

Answer 15

Double bond

Question 16

What oils formed when atoms share three pairs of electrons?

Answer 16

Triple bond

Question 17

What is average bond enthalpy?

Answer 17

Measure of average energy needed to break the bond

Question 18

What is a dative covalent bond?

Answer 18

A bond where both of the shared electrons are supplied by one atom

Question 19

How are oxonium ions formed?

Answer 19

Formed when an acid id added to water, H3O+

Question 20

What does expansion of the octet mean?

Answer 20

When a bonded atom has more that 8 electrons in the outer shell

Question 21

What are the types of covalent structure?

Answer 21

Simple molecular lattice, giant covalent lattice

Question 22

Describe the bonding in simple molecular structures

Answer 22

Atoms within the same molecule are held by strong covalent bonds and different molecules are held by weak intermolecular forces

Question 23

Why do simple molecular structures have low melting and boiling points?

Answer 23

Small amount of energy is enough to overcome the intermolecular forces

Question 24

Can simple molecular structures conduct electricity?

Answer 24

No they are non conductors