cells and electrolysis

Question 1

Metals that are hard to oxidise

Answer 1

gold and silver

Question 2

What do anodes and cathodes attract

Answer 2

anode attract anions

Cathodes attract cations

Question 3

what particles react in metals

Answer 3

Ions and electrons

Question 4

what does redox stand for

Answer 4

reduction oxidation.

Question 5

What does reduction mean

Answer 5

Reduction means electrons are gained

Question 6

what does oxidation mean

Answer 6

Oxidation means electrons are lost.

Question 7

Silver nitrate + copper =

Answer 7

copper nitrate + silver

Question 8

How is solid copper oxidised to copper ions

Answer 8

Solid copper is oxidised to copper ions by losing 2 electrons

Question 9

how are silver ions reduced to solid silver

Answer 9

Silver ions are reduced to solid silver by gaining 1 electron

Question 10

What happens when magnesium reacts with oxygen in the air

Answer 10

2Mg(s) + O2(g) ———> 2MgO(s)

The magnesium atom LOSES ELECTRONS to become a magnesium ion

Question 11

What happens when magnesium reacts with chlorine

Answer 11

So, when magnesium takes part in an oxidation reaction it loses electrons.

When magnesium reacts with chlorine it also loses electrons.

Mg(s) + Cl2(g) ———> MgCl2(s)

Question 12

what happens when lead is extracted from lead (II) oxide

Answer 12

When lead is extracted from lead (II) oxide , carbon is used to remove the oxygen
2PbO(s) + C(s) ———> 2Pb(s) + CO2(g)
The oxygen has been removed from the lead (II) oxide
The lead (II) oxide has been REDUCED

Question 13

How does lead (II) oxide form lead)

Answer 13

In the compound lead (II) oxide the lead is an ion, Pb2+

In order to form lead the Pb2+ ion has to GAIN 2 electrons

We can write this as follows:

Pb2+(s) + 2e- ——> Pb(s)

Question 14

what is redox

Answer 14

You may have noticed that when the magnesium loses its electrons they are gained by the oxygen

Oxidation (loss of electrons) and reduction (gain of electrons) happen simultaneously.

We call these REDOX reactions

Question 15

Redox simplified

Answer 15

The chemical whichgainselectrons isreduced(reducesits valency) and is called theoxidisingagent.
The chemical whichloseselectrons, isoxidised(increasesits valency) and is called thereducingagent.

Question 16

electrolysis

Answer 16

Passing an electric current through ionic substances that are molten
or in aqueous solution, breaks them down into elements.

Question 17

Electrolyte

Answer 17

Passing an electric current through ionic substances that are molten
or in aqueous solution, breaks them down into elements.
The process is known as ELECTROLYSIS

Question 18

What happens during electrolysis

Answer 18

Positively charged ions move to the negative electrode - CATHODE
Negatively charged ions move to the positive electrode - ANODE

Question 19

DO SOLID IONIC COMPOUNDS CONDUCT ELECTRICITY

Answer 19

WHEN SOLID, THE IONS
ARE NOT FREE TO MOVE
NO CONDUCTION
OF ELECTRICITY

Question 20

DO MOLTEN IONIC COMPOUNDS CONDUCT ELECTRICITY

Answer 20

WHEN MOLTEN, THE IONS
ARE FREE TO MOVE
ELECTRICITY IS
CONDUCTED

Question 21

DO AQUEOUS SOLUTIONS OF IONIC COMPOUNDS CONDUCT ELECTRICITY

Answer 21

WHEN DISSOLVED IN WATER, THE IONS ARE. FREE TO MOVE ELECTRICITY IS CONDUCTED

Question 22

DOES SOLID SODIUM CHLORIDE CONDUCT ELECTRICITY

Answer 22

SOLID SODIUM CHLORIDE DOES NOT
CONDUCT ELECTRICITY BECAUSE
THE IONS ARE NOT FREE TO MOVE
TO THE ELECTRODES

Question 23

Why is aluminium used in cars

Answer 23

It is less dense

Question 24

How are reactive metals extracted

Answer 24

Electrolysis

Question 25

Uses for chlorine

Answer 25

making bleach, making plastics such as pvc

Question 26

Uses for hydrogen

Answer 26

used as fuel

Used in margarine production

Question 27

Uses for sodium hydroxide

Answer 27

production of soaps and detergents

Used in the paper industry

Question 28

what happens to impure and pure metals in the anode and cathode

Answer 28

impure metal is oxidised at the anode

Pure metal is reduced at the cathode