Electrolysis: Mnemonics for Electrolytic Cells & Faraday’s Laws

1. Electrolysis Basics (AN OX | RED CAT)

• AN OX: Anode is where oxidation occurs.
• RED CAT: Reduction happens at the cathode.
• (Helps remember which reaction occurs at which electrode.)

2. Electrolytic Cell Setup (PANIC)

• Positive Anode, Negative Cathode (for electrolytic cells only).
• (In electrolytic cells, the anode is connected to the positive terminal, unlike in galvanic cells.)

3. Faraday’s First Law (Q = ZIt)

• “Queen Zebra Is Tall” → Q = Z I t
  • Q = Mass deposited (or liberated)
  • Z = Electrochemical equivalent
  • I = Current (in Amperes)
  • t = Time (in seconds)

4. Faraday’s Second Law (M ∝ E)

• “Moles Equal Charge per Faraday” → M = Q / (nF)
  • M = Mass deposited
  • Q = Total charge (It)
  • n = Valency number (moles of electrons)
  • F = Faraday’s constant (~96,485 C/mol)

5. Remembering Faraday’s Constant (~96,485 C/mol)

• “96,485 Cars Move On Long highways” → 96,485 C/mol (just remember the number).

6. Cathode vs. Anode in Different Cells

• Electrolytic Cell: “PANCake” → Positive Anode, Negative Cathode.
• Galvanic Cell: “NANC” → Negative Anode, Negative Cathode (but usually, the cathode is positive in galvanic cells—be careful!).

Bonus: Electrolysis of Water (OIL RIG)

• “Oxidation Is Loss, Reduction Is Gain” (of electrons).
• At the anode: 2H₂O → O₂ + 4H⁺ + 4e⁻ (Oxygen is released).
• At the cathode: 2H₂O + 2e⁻ → H₂ + 2OH⁻ (Hydrogen is released).