Redox

Question 1

OIL RIG

Answer 1

Oxidation is loss of electrons. Reduction is gain of electrons,

Question 2

How to tell if its an oxidation or reducing equation

Answer 2

Red-ox
If electrons on the left, its reduction
If electrons on the right, oxidation

Question 3

Types of redox equations

Answer 3

• Metal Displacement
• Halogen Displacement
• Disproportionation

Question 4

What reactants can undergo disproportionation

Answer 4

• 2H2O2–> 2H20 + O2

* 2Cu(+)–> Cu(2+) + Cu

Question 5

Standard reduction potentials

Answer 5

• are measured using the hydrogen half-cell as a reference cell
• 1 mol L^-1, 101.3 kPa and 25°C

Question 6

Limitations of standard reduction potentials

Answer 6

• The values of E° depend on concentration
• It applies only to aqueous solutions
• The emf of a cell can depend on temperature, pressure and acidity
• The E° gives no indication of likely reaction rate

Question 7

What are the two distinct types of electrochemical cells

Answer 7

Galvanic cells and electrolytic cells

Question 8

Galvanic cells

Answer 8

Composed of two half-cells that produce an emf

Question 9

Salt Bridge

Answer 9

Completes the circuit by allowing the migration of ions to keep the charge in both half-cells constant

Question 10

Define electrolysis

Answer 10

Electrolysis refers to the chemical changes that take place when an electrical current is passed through a molten substance or solution.

Question 11

Uses of electrolysis

Answer 11

• The extraction of metal
• Electrorefining
• Electroplating
• Anodising
• Chemical manufacture
• Recharging batteries