C3

Question 1

What are delocalised electrons?

Answer 1

Electrons which are able to move around

Question 2

What are the properties of metallic bonding?

Answer 2

• Strong forces between metal ions
• Good conductors
• Solid
• Layers can slide off eachother

Question 3

What do ionic equations show?

Answer 3

They show the useful parts of an equation

-cross out equations the same on both sides

Question 4

What are displacement reactions?

Answer 4

More reactant metals displace less reactive metals

e.g.copper sulfate + iron>iron sulfate + copper

Question 5

What happens when metals react with acids?

Answer 5

acid+metal>salt+hydrogen

The more reactive the metal, the faster the reaction will go.

Question 6

What happens when metals react with water?

Answer 6

metal+water>metal hydroxide+hydrogen

-very reactive and low reactive metals won’t react with cold water

Question 7

What is extracting metals with carbon?

Answer 7

Ores less reactive then carbon can be extracted by a displacement reaction
-During the reaction carbon is oxidised and the other metal is reduced

Question 8

What is phytoextraction?

Answer 8

Growing plants in soil which contain metal compounds
-The plants can’t get rid of the compounds so they gradually build up in leaves
The plants can be burnt-the ash will contain metal compounds which can be extracted

Question 9

What is bioleaching?

Answer 9

Using bacteria to convert insoluble compound in the ore to soluble compounds, seperating the metal and the ore

Question 10

What is a redox reaction?

Answer 10

A reaction where electrons are transferred

Question 11

What is ‘OIL RIG’

Answer 11

When dealing with electrons:
Oxidation
Is
Loss

Reduction
Is
Gain

Question 12

What do half equations show?

Answer 12

Half equations show the movement of electrons

e.g Na > Na+ + e-

Question 13

What is electrolysis?

Answer 13

During electrolysis, an electric current is passed through an electrolyte
The positive ions in the electrolyte move towards the cathode(-) and the negative ions move to the anode(+)

Question 14

What possible reaction could occur at the cathode?

Answer 14

Pb(2+) + 2e(-) > Pb

Question 15

What possible reaction could occur at the anode?

Answer 15

2Br(-) > Br2 +2e

Question 16

When is electrolysis used?

Answer 16

When the metal is too reactive to be reduced with carbon

Question 17

What happens at the cathode in an aqueous solution?

Answer 17

If H(+) ions and metal ions are present, hydrogen gas will be produced if the metal is more reactive than hydrogen
If the metal is less reactive than hydrogen, the metal will be produced

Question 18

What happens at the anode in an aqueous solution?

Answer 18

If there are chloride ions present, chlorine will be formed at the anode
If there are no chloride ions present, oxygen will be formed

Question 19

What are covalent bonds?

Answer 19

When non metals bond together, they share pairs of electrons to make covalent bonds.
Each single covalent bond provides one extra electron for each atom.

Question 20

What are the properties of simple covalent substances?

Answer 20

• Simple molecular substances
• strong covalent bonds
• weak forces
• weak intermolecular forces
• don’t conduct

Question 21

What is the empirical formula?

Answer 21

The simplest ratio of atoms.

Question 22

What is a homologous series?

Answer 22

A family of molecules which share the same general formulas and functional group.
-They share similar chemical properties.

Question 23

What happens to properties as the carbon chain gets longer?

Answer 23

• The shorter the chain, the more runny they will be

- The shorter the chain, the lower the boiling point

Question 24

What are Alkanes?

Answer 24

Homologous series.
Alkanes are hydrocarbons
Methane:CH4
Ethane:C2H6
Propane:C3C8
Butane:C4H10

Question 25

What is fractional distillation?

Answer 25

Used to separate hydrocarbons

• Oil is heated to gas
• Fractional column has condensers
• Column is heated from the bottom so there is a temperature gradient
• The hydrocarbons have boiling points which condense back into liquids and drain out of the columns.

Question 26

What are the uses of Crude Oil?

Answer 26

Provides fuel for transport
Making new compounds
Products like phones

Question 27

What is the main problem with crude oil?

Answer 27

It is a non-renewable resource

-we have to continue developing new technologies.

Question 28

What is cracking?

Answer 28

Splitting up long-chain hydrocarbons

-Hydrocarbons are heated until they become vapour which splits them up.`

Question 29

What is a functional group?

Answer 29

A group of atoms within a molecule which determines how it reacts
All members are part of the same homologous group.

Question 30

What is the main traits of alkenes?

Answer 30

They have a C-C double bond
They have twice as many hydrogens as carbons
Ethene
Propene
Butene
Penetene

Question 31

What are combustion reactions?

Answer 31

Carbohrydrate + oxygen>carbon dioxide+water

Question 32

What are additional reactions? (alkenes)

Answer 32

e.g C2H4 + H2 >C2H6
Hydrogen can react with the double-bonded carbons to open the double bond and form an alkane.

e.g.C2H4 + Br2 > C2H4Br2

Question 33

What is the alcohol functional group?

Answer 33

The O-H bond

e. g.mathanol:CH3OH
ethanol: C2H5OH

Question 34

What are alcohols?

Answer 34

Industrial solvents that are able to dissolve in things water can’t.

Question 35

What is the functional group of carboxylic acids?

Answer 35

They have the functional group COOH
e.g.HCOOH
CH3COOH