Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GCSE CCEA Chemistry unit 2 And 3 > Electrochemistry > Flashcards

Electrochemistry Flashcards

1
Q

What is Electrolysis? (3)

A
  • The decomposition
  • of electrolytes
  • using electricity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are Electrolytes (3)

A
  • An ionic liquid or solution
  • that conducts electricity
  • and is decomposed during electrolysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the name of a positive electrode?

A

Anode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the name of a negative electrode?

A

Cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the pneumonic for remembering the charge of each electrode?

A

Positive electrode
Anode
Negative
Is
Cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why is heat applied to an electrolyte during electrolysis? (2)

A

In order to change the
- solid ionic compound into a liquid
- where the ions are free to move and carry a charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give two half equations which demonstrate electrolysis in

LiCl

A
  • Li+ + e- —> Li
  • 2Cl- —> Cl2 + 2e-
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What state are metals after electrolysis generally?

A

Liquid, usually a grey colour as well

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What electrode are anions and cations attracted to?

A
  1. anion (negative ion) - anode (positive electrode)
    An-an
  2. cation (positive ion) - Cathode (negative electrode)
    Cat-cat

In both cases:
- both are oppositely charged
- electrostatic attraction pulls them together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the common name for aluminium ore?

A

Bauxite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When do Metals require electrolysis to extract

A

If they are more reactive than carbon, or react with carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In the electrolysis of Lithium Chloride, what electrode are the Li+ and Cl- ions attracted to?

A
  • Li+ —> Cathode
  • Cl- —> Anode
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give 2 Reasons electrolysis requires lots of energy

A
  • To melt the compound
  • to produce the electrical current
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the Mixture used in electrolysis of aluminium

A
  • Cryolite
  • Aluminium oxide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What apparatus is used in the electrolysis of Lead Bromide and Lithium Chloride (7)

A
  • a power source
  • evaporating basin or crucible
  • tripod
  • gauze
  • heat source
  • bulb on negative side of circuit
  • the actual electrolyte
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is Cryolite added to bauxite?

A
  • To lower the melting point of aluminium oxide and
  • increase its electrical conductivity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why is there a bulb in the circuit of electrolysis equipment?

A

If the circuit is complete, the bulb lights up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is The material of the anode for aluminium extraction

19
Q

Why does the anode require regular replacement in aluminium extraction (2)

A
  • high temp causes
  • Oxygen produced at the anode, to react with graphite (CO2 formed) in the anode, wearing it away
20
Q

What type of reaction is the electrolysis of lithium chloride?

A

Redox:

  • lithium gains electron - reduction
  • chloride ions lose electrons - oxidation
21
Q

What is formed at the anode by aluminium extraction

22
Q

What is formed at the cathode by aluminium extraction

A

Molten aluminium

23
Q

What are the observations at the anode in the electrolysis of lithium chloride?

A
  • yellow-green gas
  • pungent smell
24
Q

How do you recycle Aluminium (4)

A
  • Shred
  • remove coating
  • melt
  • cast (into ingots)
25
What is the **observation** at the **cathode** in the **electrolysis of lithium chloride**?
**Molten** grey liquid
26
What are the **Advantages** of **recycling Aluminium** (**give 2**)
- Reduces the energy required - cheaper - aluminium is a finite resource - prevents waste from going to landfill - better for the environment: 1. does not involve mining methods 2. Less greenhouse gas emissions through energy production
27
In the electrolysis of **Lead Bromide**, what electrode are the **Pb2+ and Br-** ions attracted to?
- Pb2+ —> cathode - Br- —> anode
28
What **type of reaction** is the **electrolysis** of **lead bromide**?
Redox: - lead gains electrons- reduction - bromide ions lose electrons - oxidation
29
What are the **observations** at the **anode** in the **electrolysis of lead bromide**?
- **red-brown** gas - pungent smell
30
What is the **observation** at the **cathode** in the **electrolysis of lead bromide**?
**Molten** grey liquid drops formed
31
**What functions as the cathode** in the *electrolysis* of **bauxite**?
The **graphite lining** of the container
32
Where does the **aluminium** go **after the electrolysis** of bauxite (**2**)
- sinks to the bottom of the container - is tapped off
33
In the **electrolysis** of **dilute sulphuric acid** what are the **products** formed at the **anode**
Oxygen and water
34
In the **electrolysis** of dilute **sulphuric acid** what is the **product** formed at the **cathode**
Hydrogen
35
What happens to the **sulphate ion** in the electrolysis of H2SO4
It is unchanged
36
In the electrolysis of **dilute sulphuric acid**, what electrode are the **H+ and OH- and SO4-** ions attracted to?
- H+ —> Cathode - OH- and SO4-—> Anode
37
What happens to the **OH- ion** in the electrolysis of H2SO4
It is **preferentially discharged**
38
What is the **half equation** at the **anode** in the electrolysis of H2SO4
4OH- —> O2 + 2H2O + 4e-
39
What is the **half equation** at the **cathode** in the electrolysis of H2SO4
H2 —> 2H+ + 2e-
40
What **type of reaction** is the **electrolysis** of **sulfuric acid**?
Redox: - H+ ions gain electrons - reduction - OH- ions lose electrons - oxidation
41
What is preferential discharge? (**2**)
- if **more than one** type of **ion** is attracted towards a particular **electrode** - **the one discharged** is the ion that **requires the least energy**
42
Why is **graphite** used for **electrodes**? (**3**)
- *relatively* inert - **high m.p.** - conducts electricity
43
**Why** does an **electrolyte** need to be an **ionic compound** that’s **molten** or **in solution**?
So the **ions** can **move** and **carry a charge**
44
What happens to **electrolytes** when they **conduct electricity**?
They decompose

GCSE CCEA Chemistry unit 2 And 3 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions