C2

Question 1

What is ionic bonding?

Answer 1

Metals bonded to non-metals. Atoms become charged either by losing or gaining electrons.

Question 2

What is covalent bonding?

Answer 2

Occurs between two non-metals when atoms share electrons to achieve a full outer shell.

Question 3

What is metallic bonding?

Answer 3

Occurs between metal atoms. Electrons become de-localised and free to move (a sea of free electrons is created).

Question 4

What type of structure does ionic bonding have?

Answer 4

lattice

Question 5

What type of structure does covalent bonding have?

Answer 5

simple molecular and Giant molecular

Question 6

What type of structure does metallic bonding have?

Answer 6

lattice. There is a strong electrostatic attraction between the ‘sea’ of negatively charged electrons and positive metal ions.

Question 7

Why do ionic compounds have a high melting point?

Answer 7

They have a strong electrostatic attraction between two oppositely charged ions and therefore requires lots of energy to break.

Question 8

What substances have a giant covalent structure?

Answer 8

Diamond, graphite, SiO2 (silica)

Question 9

What are the properties of a giant covalent structure?

Answer 9

• Many strong covalent bonds which are difficult to break and require lots of energy to do so.
• Each atom is bonded to four atoms creating an interconnected lattice where no atom can move independently from each other.
• does not have layers so cannot slide
• no free electrons

Question 10

What are the properties of graphite?

Answer 10

• conducts electricity as it has free electrons
• each atom is bonded to three others creating a layered structure with weak intermolecular forces between the layers allowing them to slide over each other

Question 11

What are polymers ?

Answer 11

made of many monomers and produced from cracking and alkenes.

Question 12

What is polymerisation?

Answer 12

when many monomers form a long chain called a polymer (a much more useful substance)

Question 13

Compare High Density Polyethene to Low Density Polyethene

Answer 13

hdpe will pack together tighter as the polymers can line up easily. Therefore, hdpe will be able to form a higher number of intermolecular bonds and will have a higher melting point as more energy is required to break the bonds.

Question 14

The properties of polymers depend on:

Answer 14

what they are made from (monomers)

and the conditions in which they were made ( eg hdpe and ldpe)

Question 15

Describe thermosoftening

Answer 15

Good if wanting to recycle the plastic as they are easy to separate due to the weak intermolecular forces being broken down and heated. When a polymer cools intermolecular forces pull the molecules back together hence it can be re-shaped

Question 16

Describe thermosetting

Answer 16

polymers fixed together by strong covalent bonds and stop the polymers being separated. When heated strongly the polymers will char.

Question 17

Whats nanotechnology?

Answer 17

nanoparticles are particles sized between 1 and 100 nanometres. This is roughly 100 atoms in size

Question 18

what is collision theory?

Answer 18

in order for a reaction to occur, the reacting particles must collide with enough energy to react

activation energy is the minimum amount

Question 19

how does increasing pressure increase rates?

Answer 19

increased collisions=quicker rate

same no.of atoms, smaller volume

Question 20

how does increasing concentration increase the rate?

Answer 20

more particles, more collisions, increased rate

Question 21

what is effect 1 of increasing temperature?

Answer 21

atoms have more energy, move faster, more collisions, more reactions

Question 22

what is effect 2 of increasing temperature?

Answer 22

atoms have more energy, more have sufficient energy to react, more numbers of successful collisions, increased rate of reaction

Question 23

how does surface area affect rates?

Answer 23

bigger area available to react, increased frequency, increased rate

Question 24

how does adding a catalyst affect rates?

Answer 24

lowers activation energy, successful collisions increase, rate of reaction increases

Question 25

acid + metal = ????????????

Answer 25

salt + hydrogen

Question 26

acid + base = ????????????

Answer 26

salt + water

Question 27

what is an acid + base and acid + metal carbonate reaction?

Answer 27

neutralization reaction

Question 28

acid + metal carbonate = ????????????

Answer 28

salt + carbon dioxide + water

Question 29

what is a soluble salt

Answer 29

dissolves in water

Question 30

what is an insoluble salt?

Answer 30

doesnt dissolve in water

Question 31

what is precipitation?

Answer 31

removing ions from a solution. To remove an ion from a solution, you need to form an insoluble salt of it. The precipitate can then be filtered off.

Question 32

how do you make ammonium nitrate

Answer 32

ammonia dissolves in water to form alkaline ammonium hydroxde. ( NH3+H2O=NH4+OH-)
ammonium hydroxide + nitric acid = water + ammonium nitrate