Topic 3 - Structure and Bonding

Question 1

What are the three states of matter? (excluding plasma)

Answer 1

Solid, liquid and gas.

Question 2

What is the structure of a solid like?

Answer 2

They have a fixed shape and volume and cannot be compressed.

Question 3

What is the structure of a liquid like?

Answer 3

They have a fixed volume but can flow and change their shape.

Question 4

What is the structure of gases like?

Answer 4

They have no fixed volume or shape and can be compressed easily.

Question 5

Which state of matter is the most densely packed and rigid?

Answer 5

Solid.

Question 6

What state of matter contains weaker bonds and a less rigid structure?

Answer 6

Liquid.

Question 7

A solid turns into a liquid when?

Answer 7

When it reaches its melting point.

Question 8

A liquid boils into a gas when?

Answer 8

When it reaches its boiling point.

Question 9

The hotter a substance is the _______ its particles move. What word finishes the sentence?

Answer 9

Faster.

Question 10

Each change of state can be?

Answer 10

Reversed.

Question 11

Non-metals’ bonds are normally?

Answer 11

Covalent bonds.

Question 12

Metal’s bonds are normally?

Answer 12

Ionic bonds.

Question 13

Covalent bonding is where elements?

Answer 13

Share electrons between them to complete their outer shell.

Question 14

Ionic bonding is where?

Answer 14

An element that needs to gain an electron is given an electron by an element that needs to lose one.

Question 15

When an element loses an electron what happens to its overall charge and why?

Answer 15

The element becomes positively charged as there is more protons than electrons as the proton number stays the same.

Question 16

When an element gains an electron what happens to its overall charge and why?

Answer 16

The element becomes negatively charged as there are now more electrons than protons as the proton number stays the same.

Question 17

When Chlorine (atomic number 17) reacts with Sodium (atomic number 11) they change their electronic structures. Explain how this structure changes and why.

Answer 17

Chlorine turns from structure 2,8,7 to 2,8,8 as it gains an electron from Sodium, completing its outer shell. Sodium loses an electron to give to Chlorine and thus its structure goes from 2,8,1 to 2,8.

Question 18

When Sodium and Chlorine react, they become ionic, write an ion of Sodium and one of Chlorine and explain why they have this formula.

Answer 18

Sodium loses an electron, thus there are more Protons than Electrons and it now has a positive charge. It is thus written as Na+. Chlorine gains an electron, thus there are more Electrons than Protons and it has a negative charge. Therefore it is written as Cl-

Question 19

Ionic bonds lead to a structure called a?

Answer 19

Giant lattice.

Question 20

Why does it take a high amount of energy to break a giant ionic lattice?

Answer 20

They have many strong ionic bonds to break.

Question 21

Why are ionic substances able to be dissolved in water?

Answer 21

They gain the energy to move to the electrodes and carry their opposite charge with them. For example in MgCl,Mg2+ ions would go to the cathode.

Question 22

What is a covalent bond?

Answer 22

A bond where two non-metals share an electron between them. For example H2O has 2 Hydrogen atoms which both share and electron with the Oxygen atom.

Question 23

What causes covalent bonds to be weak?

Answer 23

They have weak intermolecular forces between them.

Question 24

What are polymers?

Answer 24

Long chains of reactive molecules that bond together to make long chains.

Question 25

What are two examples of giant covalent structures?

Answer 25

Diamond and Graphite.

Question 26

Graphite and Diamond are made from many of what element?

Answer 26

Carbon.

Question 27

How many carbons are bonded to each carbon atom in Diamond and in Graphite? What does this lead to Graphite having?

Answer 27

Diamond has 4 electrons bonded to each carbon atom whereas Graphite only has 3 carbons bonded to each one. Since carbon requires 4 electrons to complete its outer shell, Graphite has delocalised electrons and is able to conduct electricity.

Question 28

What are some of the properties of giant covalent structures?

Answer 28

1) They have very high melting/boiling points due to their large amount of bonds.
2)They are insoluble in water.
3) Apart from Graphite, they are hard and do not conduct electricity.

Question 29

What is metallic bonding?

Answer 29

Where many positively charged metal ions bond together in a lattice. They conduct electricity since they have delocalised electrons.

Question 30

Why are Nanoparticles used in reactions?

Answer 30

Due to their small size, Nanoparticles have a high SA to volume ratio and thus react much faster than bulk materials.

Question 31

Name three applications of nanotechnology.

Answer 31

1) Glass is coated with titanium oxide Nanoparticles, these remove dirt when sunshine hits them.
2) Titanium oxide Nanoparticles are used as sunscreen to absorb UV rays and prevent skin cancer.
3) The skincare industry uses nanotechnology to absorb products through the pores in the skin.

Question 32

What are fullerenes?

Answer 32

Spherical formations of carbon atoms like buckminsterfullerene.

Question 33

What are two properties of fullerenes?

Answer 33

1) They have high tensile strength leading to being used in tennis rackets for example.
2) They have high electrical and thermal conductivity.

Question 34

When and what was the first fullerene discovered?

Answer 34

Buckminsterfullerene in 1985.

Question 35

What is graphene?

Answer 35

A layer of graphite which is very good at conducting electricity and could help scientists in the future with new technology.