R-ATCHE-1

Class Date: 2023-02-02

Commercial Cells

Carbon rod used in dry cell because it is inert, provides pathway for electrons for Manganese dioxide mixture surrounded in ammonium chloride paste - Cathode(site of reduction)

The negative terminal is the zinc container - Anode(site of oxidation)

Primary cell: Not rechargeable Secondary cell: Rechargeable

In the dry cell the Zinc slowly dissolves over time, and the Ammonia will leak out. In a secondary cell the reagents/products stay in place and the process can be reversed via electrolysis to recharge the process.

Hydrogen Fuel Cell

Electrodes usually made of graphite External circuit still present! Overall reaction: Hydrogen + Oxygen = Water

• Fuel cell = efficient way of doing combustion, we don't lose energy as heat instead it is fully converted to electrical energy

$O_{2(g)} + 2H_{2}O_{(l)} + 4\overline{e} \to 2H_{2}O_{(l)}$ $H_{2} \to 2H^{+} + 2\overline{e}$

Electrolytes are necessary as they can distribute to balance out changes, allowing the circuit to complete.

Electrodes must be porous, bigger surface area is better for the gas.

Notes:

• Use effervescence
• "Salmon pink solid is deposited on salmon pink electrode" - observation for copper electrorefining,
  • Solution doesn't changed, when copper ions are formed they are consumed.
• Anode mud (?)
• Sometimes if concentrations are too low, diffusion/ion migration does not keep up with the rate of redox, hence the voltage is lower than expected. Pranav suggestion: Instead of "anodic electrode", write "positive electrode". :)

Backlinks

Recent pages

None found yet.