Chemistry > Electrolysis > Flashcards

Electrolysis Flashcards

(55 cards)

Study These Flashcards
1
Q

Define electrolysis

A

Electrolysis is the process of using an electric current to decompose or break down a molten or aqueous ionic compound.

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

True or False?

The electrodes used in electrolysis must be inert.

A

True.

The electrodes used in electrolysis must be inert.

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

What is the electrolyte?

A

The electrolyte is the ionic compound in molten or dissolved solution that conducts the electricity.

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

What is the anode?

A

The anode is the positive electrode.

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

What is the cathode?

A

The cathode is the negative electrode.

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

Which way do electrons flow in the circuit during electrolysis?

A

Electrons flow from the anode to the cathode.

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

Why are cations attracted to the cathode?

A

Positive cations are attracted to the negatively charged cathode because opposite charges attract.

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

Why are anions attracted to the anode?

A

Negative anions are attracted to the positively charged anode because opposite charges attract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

True or False?

The electrolyte must be solid or molten to undergo electrolysis.

A

False.

The electrolyte must be molten or in solution to undergo electrolysis.

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

Why do most covalent compounds not conduct electricity?

A

Most covalent compounds do not conduct electricity because they have no freely moving ions to carry the current.

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

What is produced at the cathode during electrolysis of molten lead(II) bromide?

A

Molten lead is produced at the cathode during electrolysis of molten lead(II) bromide.

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

What is produced at the anode during electrolysis of molten lead(II) bromide?

A

Brown fumes of bromine gas are produced at the anode during electrolysis of molten lead(II) bromide.

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

What would be the products of electrolysis of molten zinc chloride?

A

The products of electrolysis of molten zinc chloride would be zinc at the cathode and chlorine at the anode.

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

What type of electrodes are typically used in the electrolysis of molten compounds?

A

Graphite or platinum electrodes are typically used in the electrolysis of molten compounds.

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

Why do molten ionic compounds conduct electricity?

A

Molten ionic compounds conduct electricity because their ions can move freely and carry the current.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Explain how a molecule of chlorine forms during the electrolysis of lead(II) chloride.

A

Two chloride ions are attracted to the anode where they each lose one electron.

They bond to form a molecule of chlorine.

2Cl- ⟶ Cl2 + 2e-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What determines the method of extraction for a metal?

A

The position of the metal on the reactivity series determines the method of extraction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

True or False?

The positive ion will migrate towards the cathode and the negative ion will migrate towards the anode.

A

True.

The positive ion will migrate towards the cathode and the negative ion will migrate towards the anode.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

True or False?

The cathode product will always be the non-metal and the product formed at the anode will always be the metal.

A

False.

The cathode product will always be the metal l and the product formed at the anode will always be the non-metal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the main ore of aluminium?

A

The main ore of aluminium is bauxite, which contains aluminium oxide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is electrolysis used to extract metals above carbon in the reactivity series?

A

Electrolysis is used to extract metals above carbon in the reactivity series because they are too reactive to be reduced by carbon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

True or False?

Electrolysis is a cheap method of metal extraction.

A

False.

Electrolysis is very expensive as large amounts of energy are required to melt the ores and produce the electrical current.

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

Why is cryolite used in the extraction of aluminium?

Study These Flashcards
A

Cryolite is used in the extraction of aluminium because it lowers the melting point of aluminium oxide without interfering with the reaction, reducing energy costs.

19
Q

What is produced at the negative electrode (cathode) during the extraction of aluminium?

Study These Flashcards
A

Aluminium is produced at the cathode during the extraction of aluminium.

20
What is produced at the positive electrode (anode) during the extraction of aluminium?
Oxygen is produced at the anode during the extraction of aluminium.
21
Why does the anode need to be replaced regularly in aluminium extraction?
The anode needs to be replaced regularly in aluminium extraction because the carbon in the graphite anodes reacts with the oxygen produced to form CO2, causing the anode to wear away.
22
What is the equation for the reaction at the anode in aluminium extraction?
The equation for the reaction at the anode in aluminium extraction is: C (s) + O2 (g) → CO2 (g)
22
True or False? Metals below carbon in the reactivity series can be extracted by heating with carbon.
True. Metals below carbon in the reactivity series can be extracted by heating with carbon.
23
Write the half equation for the reduction of aluminium ions at the negative electrode.
The half equation for the reduction of aluminium ions at the negative electrode is: Al3+ + 3e– ⟶ Al
24
What ions are always present in aqueous solutions?
Aqueous solutions always have H+ and OH- ions present from the splitting of water molecules.
24
Write the half equation for the oxidation of oxide ions at the positive electrode.
The half equation for the oxidation of oxide ions at the positive electrode is: 2O2- ⟶ O2 + 4e–
25
What ions are attracted to the positive electrode?
Negatively charged OH- ions and non-metal ions are attracted to the positive electrode.
26
True or False? If halide ions are present in the aqueous electrolyte, they are discharged at the anode.
True. If halide ions are present in the aqueous electrolyte, they are discharged at the anode.
27
What gas is produced at the anode if no halide ions are present in the electrolyte?
If no halide ions are present, OH- is discharged at the anode, forming oxygen gas.
28
What ions are attracted to the negative electrode?
H+ ions and metal ions are attracted to the negative electrode.
29
How is the product at the cathode determined?
The product at the cathode is determined by the position of the metal in the reactivity series relative to hydrogen.
30
True or False? Copper is produced at the cathode during electrolysis of copper chloride solution.
True. Copper is produced at the cathode during electrolysis of copper chloride solution.
30
What is produced at the cathode during electrolysis of sodium chloride solution?
Hydrogen gas is produced at the cathode during electrolysis of sodium chloride solution.
31
What are the products of electrolysis of sodium sulfate solution?
The products of electrolysis of sodium sulfate solution are hydrogen at the cathode and oxygen at the anode.
32
What determines which ions are discharged at the electrodes during electrolysis of aqueous solutions?
The relative reactivity of the elements involved determines which ions are discharged at the electrodes during electrolysis of aqueous solutions.
33
What are the products of electrolysis of acidified water?
The products of electrolysis of acidified water are hydrogen at the cathode and oxygen at the anode.
34
True or False? Metals above hydrogen in the reactivity series will be produced at the cathode during electrolysis of their aqueous solutions.
False. For metals above hydrogen in the reactivity series, hydrogen gas will be produced at the cathode instead of the metal.
35
Define oxidation in terms of electron transfer.
Oxidation is when a substance loses electrons.
36
Define reduction in terms of electron transfer.
Reduction is when a substance gains electrons.
36
What happens at the anode during electrolysis?
At the anode, negatively charged ions lose electrons and are therefore oxidised.
37
What happens at the cathode during electrolysis?
At the cathode, positively charged ions gain electrons and are thus reduced.
38
What is a half equation?
A half equation is an equation that describes the movement of electrons at each electrode during electrolysis.
38
State the half equation for the reduction of Pb2+ ions at the cathode.
The half equation for the reduction of Pb2+ ions at the cathode is: Pb2+ + 2e- → Pb
39
State the half equation for the oxidation of Br- ions at the anode.
The half equation for the oxidation of Br- ions at the anode is: 2Br- → Br2 + 2e-
40
True or False? In half equations, the charges on each side of the equation should always balance.
True. In half equations, the charges on each side of the equation should always balance.
40
State the half equation for the reduction of hydrogen ions at the cathode in aqueous solutions.
The half equation for the reduction of hydrogen ions at the cathode in aqueous solutions is: 2H+ + 2e- → H2
41
Balance the half equation for the oxidation of water molecules at the anode in acidic solutions: .... H2O → O2 + .... H+ + .... e-
The balanced half equation for the oxidation of water molecules at the anode in acidic solutions is: 2H2O → O2 + 4H+ + 4e-
42
Write the ionic half-equation for the reduction of copper(II) ions.
The half equation for the reduction of copper(II) ions is: Cu2+ + 2e- → Cu
43
Write the ionic half- equation for the reduction of Sn2+ ions at the cathode?
The ionic half- equation for the reduction of Sn2+ ions is: Sn2+ + 2e- → Sn
43
Write the ionic half-equation for the oxidation of chloride ions.
The half equation for the oxidation of chloride ions is: 2Cl- → Cl2 + 2e-
Chemistry
flashcards
Decks in class (27)
# Cards
Brainscape helps you reach your goals faster, through stronger study habits.
© 2026 Bold Learning Solutions. Terms and Conditions