(A1) Electrolysis Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is electrolysis?

A

When a current is passed through a substance, causing the substance to decompose

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

What is electrolysis used for?

A

To break apart ionic compounds

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

What state does a substance have to been in for electrolysis?

A

A substance must be dissolved (aqueous) in solution or be a liquid (molten)

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

Why must the substance in electrolysis be dissolved?

A

So that the ions are free to move and can conduct

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

What is the positive electrode?

A

Anode

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

What is the negative electrode?

A

Cathode

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

What is a cation?

A

A positively charged ion that would be attracted to the cathode

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

What is an anion?

A

A negatively charged ion that would be attracted to the anode

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

What happens at the anode?

A

Negative ions lose electrons (they are oxidised)

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

What happens at the cathode?

A

Positive ions gain electrons (they are reduced)

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

Which cation will go to the cathode?

A

H+ (unless it is gold, copper or silver) because it is lower in the reactivity series

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

At the anode what happens if there is an halide(group 7) ion?

A

A halogen will form (Cl2 or Br2)

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

What happens at the anode if there is no halide?

A

Oxygen gas is formed

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

What is the equation for oxygen gas?

A

40H- –> O2 +H20 + 4e-

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

What is an electrolyte?

A

An ionic compound solution (a liquid that can conduct electricity)

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

What is brine?

A

Aqueous sodium chloride

17
Q

What products are made from brine?

A
  • Chlorine Gas
  • Hydrogen Gas
  • Sodium Hydroxide Solution
18
Q

What is the undesirable product that comes from brine?

A

Chlorine Gas (poisonous)

19
Q

What is the use of the hydrogen that comes from brine?

A

In hydrogen fuel cells and the manufacture of butter

20
Q

What is the use of the chlorine that comes from brine?

A

In swimming pools to kill microbes

21
Q

What is sodium hydroxide used for?

A

To neutralise acids and extract alumina from it’s ore

22
Q

What is a diaphragm or membrane cell used for?

A

To prevent undesirable products