Bonding And Structure Chemistry

Question 1

What are the 3 states of matter

Answer 1

Solid liquid and gas

Question 2

Describe a Solid

Answer 2

strong force of attraction, cant flow or move only vibrate, fixed lattice arrangement, cant be compressed and expand slightly when heated

Question 3

Describe a Liquids

Answer 3

weak force of attraction, irregular structure, can flow and take shape of containers, can be compressed, expand when heated

Question 4

Describe a gas

Answer 4

very weak force, free and far apart, constantly moving in random directions, can be compressed, speed up when heated

Question 5

What is ionic bonding?

Answer 5

When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms, forming ions. The resulting compound is called an ionic compound. Reactions between metals and non-metals include: sodium + chlorine → sodium chloride.

Question 6

Ionic compounds form what?

Answer 6

Giant structures where every positive ion is surrounded by a negative ion - this is called a giant ionic lattice

Question 7

What are the characteristics of a giant ionic lattice

Answer 7

Three dimensional
Strong forces of attraction between the positive and negative ions these are called electrostatic forces

Question 8

What are the key properties of ionic compounds?

Answer 8

Very high melting and boiling points because strong electrostatic forces require a great deal of heat energy to break.
Cannot conduct electricity when they are solids because the ions cannot move. They are locked in place by the strong electrostatic forces of attraction
Can conduct electricity when they are melted or dissolved in water because the ions can now move and carry the charge

Question 9

What is covalent bonding?

Answer 9

A covalent bond forms when two non-metal atoms share a pair of electrons . The electrons involved are in the outer shells of the atoms. An atom that shares one or more of its electrons will complete its outer shell. Covalent bonds are strong – a lot of energy is needed to break them.

Question 10

What is diamond made from?

Answer 10

Carbon atoms

Question 11

Each carbon atom in a diamond has how many strong covalent bonds?

Answer 11

Four

Question 12

Diamond cannot what? Why?

Answer 12

Conduct electricity as there are no free electrons to carry electrical charge

Question 13

silicon dioxide has a what? Why?

Answer 13

Very high melting and boiling point due to a huge number of strong covalent bonds that must be broken which takes a great deal of energy

Question 14

Graphite is an excellent conductor of what two things?

Answer 14

Electricity and heat

Question 15

In the case of graphite each carbon atom forms how many covalent bonds?

Answer 15

Three

Question 16

The hexagonal rings of carbon atoms are arranged in what?

Answer 16

Layers- there are no covalent bonds between the layers so they can slide this makes graphite slippery

Question 17

What are delocalised electrons?

Answer 17

Electrons that are not attached to any individual atom so are free to move

Question 18

Why do we use to make a mixture harder?

Answer 18

An alloy

Question 19

What is an alloy?

Answer 19

A mixture of metals

Question 20

What is metallic bonding

Answer 20

Metallic bonding is a type of chemical bonding that arises from the electrostatic attractive force between conduction electrons and positively charged metal ions. It may be described as the sharing of free electrons among a structure of positively charged ions.

Metallic bonding is the electrostatic attraction between positive metal ions and delocalised electrons. The organisation of the metal ions and the free-moving electrons give metals certain properties, such as malleability and ability to conduct heat and electricity.

Question 21

Properties of covalent bonding

Answer 21

The boiling/melting points of covalent compounds are low.
They are soft in nature and relatively flexible.
These compounds do not possess electrical conductivity.
They have lower values of enthalpy of fusion/vaporization

Question 22

Properties of ionic bonding

Answer 22

high melting and boiling points, poor conductivity in solid state, and high conductivity in aqueous solutions. →How does Ionic Bonding

Question 23

Properties of metallic bonding

Answer 23

strong, so metals can maintain a regular structure and usually have high melting and boiling point

Question 24

How can you use the periodic table to help you remember charges on ions?

Answer 24

Look at the group number:
Group 1 form +1 ions
Group 2 = +2
Group 3 = +3
Group 4 = don’t form ions
Group 5 = -3
Group 6 = -2
Group 7 = -1
Group 0 don’t form ions

Question 25

What are the two types of covalent structures?

Answer 25

Giant covalent and simple molecular structures

Question 26

What are the properties of simple molecular substances?

Answer 26

Gases, liquids (with low boiling points) or solids (with low melting points), usually non conductors.

Question 27

Why do simple covalent compounds have low melting and boiling points?

Answer 27

They have weak forces of attraction between their molecules that take little energy to overcome.

Question 28

What are the properties of giant covalent structures?

Answer 28

Solids with very high melting and boiling points.

Question 29

What are some examples of giant covalent structures?

Answer 29

Diamond, graphite (both forms of carbon), silicon dioxide (sand)

Question 30

Describe the structure of diamond and graphite.

Answer 30

Diamond-each carbon atom forms 4 covalent bonds to other carbon atoms forming a rigid, giant 3D structure.
Graphite-each carbon only forms 3 covalent bonds to other carbons, creating layers of hexagons between which there are delocalised electrons (one e- per carbon).

Question 31

Why do metals conduct electricity?

Answer 31

They have delocalised electrons which can flow when an electric field is applied across it.