Paper 2 - Electrolysis Flashcards
1
Q
Describe an experiment to investigate electrolysis of molten compounds or aqueous solutions and predict the products (e.g. Lead (II) Bromide)
A
- Place anode and cathode in molten/aqueous solution
- (following e.g.) Oxidation occurs at the anode and Bromine gas is released
- Reduction occurs at the cathode and solid lead and hydrogen gas is produced
- A brown coating can be observed at the cathode
- Fizzing and bubbling can be observed at both electrodes
2
Q
Write an ionic half equation for Chlorine ions
A
2Cl –> Cl2 + 2e-
3
Q
What does the term cathode refer to?
A
- Negatively charged electrode
- Attracts positively charged ions called anions
4
Q
Why do covalent compounds not conduct electricity?
A
There are no delocalised electrons free to flow
5
Q
Why do ionic compounds only conduct electricity when molten or in aqueous solution?
A
There is a delocalised ion free to flow
6
Q
Why is a reaction classified as a reduction reaction?
A
The atom gains electrons
7
Q
Why is a reaction classified as an oxidation reaction?
A
Atom loses electrons
8
Q
Write an ionic half equation for a Zinc ion
A
Zn2+ + 2e –> Zn
9
Q
What does the term anode refer to?
A
- Positively charged electron
- Attracts negatively charged ions called cations
