Chemistry - Topic 2 - Structure and Bonding

Question 1

Definition of a compound

Answer 1

Two or more elements which are chemically combined

Question 2

Definition of Covalent Bonding

Answer 2

Shared pair of electrons

Question 3

Definition of Ionic Bonding

Answer 3

(electrostatic) attraction between oppositely charged ions

Question 4

Describe the structure of NaCl

Answer 4

• Giant ionic lattice (structure)
• electrostatic attraction
• Between Na+ and Cl-

Question 5

Type of bonding in graphite

Answer 5

Covalent

Question 6

Describe the structure of diamond

Answer 6

Giant covalent structure where each carbon has 4 bonds

Question 7

Describe the structure of graphite

Answer 7

Giant covalent structure where each carbon has 3 bonds. It is arranged in layers.

Question 8

Definition of Metallic Bonding

Answer 8

(electrostatic) attraction between positive metal ions and the delocalised electrons

Question 9

Type of bonding in CO2

Answer 9

Covalent

Question 10

Describe the structure of CO2

Answer 10

Simple molecular

Question 11

Identify the bonding in H2O and describe its structure

Answer 11

• Covalent
• Simple molecular

Question 12

Identify the type of bonding in copper and describe its structure

Answer 12

• Metallic
• Giant metallic lattice
• Positive ions surrounded by delocalised electrons

Question 13

Identify the type of bonding in sodium chloride and describe its structure

Answer 13

• Ionic
• Giant ionic lattice
• Electrostatic attraction between positive ions and negative ions

Question 14

Identify the type of bonding in Ca(OH)2 and describe its structure

Answer 14

• Ionic
• Giant ionic lattice

Question 15

Identify the type of bonding in SiO2 and describe its structure

Answer 15

• Covalent
• Giant covalent lattice/structure (giant molecular)

Question 16

Graphite, diamond, nanotubes and fullerenes are all _________________ of carbon

Answer 16

allotropes

Question 17

Explain why NaCl is a solid at room temperature

Answer 17

• It has a giant ionic lattice
• It is held together by ionic bonds which are very strong
• and require a lot of energy to break
• Therefore it has a high melting point

Question 18

Explain why oxygen is a gas at room temperature

Answer 18

• It has a simple molecular structure
• It is held together by weak intermolecular forces
• which require little energy to overcome
• Therefore it has a low melting point

Question 19

Explain why iron is a solid at room temperature

Answer 19

• It has a giant metallic structure
• It is held together by strong metallic bonds
• Therefore it has a high melting point

Question 20

Explain why iron conducts electricity as a solid and liquid

Answer 20

It has delocalised electrons which are free to move throughout the metal structure

Question 21

Explain why graphite conducts electricity

Answer 21

• Each carbon has only 3 bonds.
• This leaves one delocalised electron
• Which is free to move throughout the structure

Question 22

Explain why diamond doesn’t conduct electricity

Answer 22

Each carbon has 4 bonds.It has no free electrons

Question 23

Explain why sodium chloride doesn’t conduct electricity as a solid

Answer 23

The ions can’t move and carry the charge

Question 24

Explain why sodium chloride conducts electricity when dissolved

Answer 24

The ions are free to move and carry the charge

Question 25

Explain why carbon dioxide doesn't conduct electricity

Answer 25

Its electrons aren't free to move and carry the charge

Question 26

Explain why molten magnesium chloride can conduct electricity

Answer 26

The ions are free to move and carry the charge

Question 27

Explain why methane is a gas at room temperature

Answer 27

* It is a simple molecular substance * It is held together by weak intermolecular forces * which require little energy to break * Therefore it has a low melting point

Question 28

Explain why graphite has a very high melting point

Answer 28

* It has a giant covalent structure * which is held together by strong covalent bonds * which require a lot of energy to break

Question 29

What property makes diamond useful for sharpening knives

Answer 29

It is very hard

Question 30

Explain why diamond is so hard

Answer 30

* It is arranged in a giant lattice * Each carbon has 4 bonds * the covalent bonds are strong

Question 31

Explain why copper is used to make wires rather than graphite

Answer 31

* Copper and graphite both conduct electricity * Copper and graphite both have a high melting point * Graphite is soft and brittle * Copper is strong and ductile

Question 32

Name properties you would expect of an ionic compound?

Answer 32

* High melting point * Doesn't conduct electricity when solid * Conducts electricity when molten or in solution

Question 33

Name properties you'd expect of a simple covalent solid

Answer 33

* Low melting point * Brittle * Dull * Soft

Question 34

Name properties you'd expect of a metal

Answer 34

* High melting point * Conducts heat and electricity * Hard * Lustrous (shiny) * Malleable (can be hammered into shape) * Ductile ( can be drawn into wires)

Question 35

What is meant by the term diatomic?

Answer 35

molecule containing two atoms

Question 36

Name the diatomic elements

Answer 36

Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine(I Bring Clay For Our New House)(Have NO Fear Ice Cold Beer)