Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Electrolysis > Flashcards

Electrolysis Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

What is electric current?

A

The flow of charged particles. Usually refers to electrons, but can also refer to the flow of ions.

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

Why don’t most covalent compounds conduct electricity?

A

They have no freely moving charged particles to carry the current. They act as insulators.

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

What are some applications of covalent compounds as insulators?

A

Used in solid, liquid, and gaseous forms as electrical insulators.

Example: Sulfur hexafluoride insulates electrical transformers. Silicone oils and liquid hydrocarbons are used in electrical equipment. Plastic coating on household electrical wiring.

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

Why can’t covalent compounds conduct electricity?

A

They lack freely moving charged particles.

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

Under what conditions can ionic compounds conduct electricity?

A

When heated beyond their melting point to become molten. This allows ions to move freely and carry charge.

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

Why can’t ionic compounds conduct electricity in the solid state?

A

The ions are in fixed positions within the lattice and cannot move.

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

What are cations and anions?

A

Anions: Negatively charged ions (e.g., Cl-, O2-, SO42-). Cations: Positively charged ions (e.g., K+, Mg2+, H+).

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

What happens during electrolysis?

A

Electrons move from the anode towards the cathode. Cations migrate towards the cathode (negative electrode). Anions migrate towards the anode (positive electrode).

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

Why are cations attracted to the cathode and anions to the anode during electrolysis?

A

Because of their opposite charges.

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

What is the main concern in electrochemistry?

A

The transfer of electrons.

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

How are oxidation and reduction defined in electrochemistry?

A

Oxidation: Loss of electrons. Reduction: Gain of electrons.

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

What happens when ions come into contact with the electrodes during electrolysis?

A

Electrons are either lost or gained, forming neutral substances which are discharged as products at the electrodes.

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

What happens at the anode during electrolysis?

A

Negatively charged ions lose electrons and are oxidized.

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

What happens at the cathode during electrolysis?

A

Positively charged ions gain electrons and are reduced.

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

What are half equations in electrochemistry?

A

Equations that describe the movement of electrons at each electrode.

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

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

A

Pb2+ + 2e– ⟶ Pb (Reduction)

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

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

A

2Br– – 2e– ⟶ Br2 (Oxidation)

OR 2Br– ⟶ Br2 + 2e–

18
Q

What is the half equation at the cathode during the electrolysis of aqueous sodium chloride?

A

2H+ + 2e– ⟶ H2 (Reduction)

19
Q

What is the half equation at the anode during the electrolysis of aqueous sodium chloride?

A

2Cl– – 2e– ⟶ Cl2 (Oxidation)

OR 2Cl– ⟶ Cl2 + 2e–

20
Q

What is the half equation at the cathode during the electrolysis of dilute sulfuric acid?

A

2H+ + 2e– ⟶ H2 (Reduction)

21
Q

What is the half equation at the anode during the electrolysis of dilute sulfuric acid?

A

2H2O – 4e– ⟶ O2 + 4H+ (Oxidation)

OR 2H2O ⟶ O2 + 4H+ + 4e–

22
Q

What is the half equation at the cathode during the electrolysis of aqueous copper(II) sulfate?

A

Cu2+ + 2e– ⟶ Cu (Reduction)

23
Q

What is the half equation at the anode during the electrolysis of aqueous copper(II) sulfate?

A

2H2O – 4e– ⟶ O2 + 4H+ (Oxidation)

OR 2H2O ⟶ O2 + 4H+ + 4e–

24
Q

What is the aim of the experiment involving electrolysis of aqueous solutions?

A

To electrolyse aqueous solutions of sodium chloride, sulfuric acid, and copper(II) sulfate. To collect and identify the products at each electrode.

25
Q

How can gaseous products be collected during electrolysis?

A

By using inverted test tubes above the electrodes to collect the gases.

26
Q

What is the method for performing electrolysis of aqueous solutions?

A

Add the aqueous solution to a beaker and cover the electrodes with the solution. Invert two small test tubes to collect any gaseous products. Connect the electrodes to a power pack or battery. Turn on the power pack or battery and allow electrolysis to take place. Make observations at each electrode.

27
Q

How can the products at each electrode be identified?

A

Gases collected in the test tube can be tested and identified.

28
Q

How can you test if the gas produced at the cathode is hydrogen?

A

If the gas burns with a ‘pop’ when a sample is lit with a lighted splint, the gas is hydrogen.

29
Q

How can you test if the gas produced at the anode is oxygen?

A

If the gas relights a glowing splint dipped into a sample, the gas is oxygen.

30
Q

How can you test if the gas produced at the anode is chlorine?

A

If the gas bleaches a piece of litmus paper, chlorine has been produced.

31
Q

How can you test if a metal has been formed at the electrode?

A

If a solid forms around the electrode, the metal has been produced. The color of the solid can indicate the metal formed.

32
Q

What is oxidation?

A

• Gain of oxygen.
• Loss of electrons.

33
Q

What is reduction?

A

• Loss of oxygen.
• Gain of electrons.

34
Q

What is a redox reaction?

A

• A reaction where oxidation and reduction happen together.

35
Q

What is an oxidizing agent?

A

• Causes oxidation.
• Accepts electrons (is reduced).
• Supplies oxygen.

36
Q

What is a reducing agent?

A

• Causes reduction.
• Donates electrons (is oxidized).
• Removes oxygen.

37
Q

Key mnemonic for oxidation/reduction?

A

• OIL RIG:
• Oxidation Is Loss (of electrons).
• Reduction Is Gain (of electrons).

38
Q

Example of oxidation (with oxygen)?

A

• Magnesium gains oxygen → it is oxidized.

39
Q

Example of reduction (with oxygen)?

A

• Copper(II) oxide loses oxygen → it is reduced.

40
Q

Example of a redox reaction?

A

• Zinc is oxidized (loses electrons).
• Copper is reduced (gains electrons).

Chemistry (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions