Educator

Practical Batteries, Electrolysis

• Primary batteries: dry cell; alkaline battery; fuel cell

• Secondary batteries: lead-acid, Nicad; lithium ion

• Electrolysis: breaking down compounds by electric current

• Examples of electrolysis: Na and Cl₂ from fused NaCl; NaOH and Cl₂ from salt solution; copper refining; metal plating

• Faraday = 96,500 coulombs = 96,500 As

• Do examples of quantitative use of Faraday’s Laws e.g. Al production

• Corrosion of iron is an electrolytic process: needs both H₂O and O₂

• Can protect iron by coatings and sacrificial Zn electrodes