Electrochemistry

• Oxidation: Loss of electrons by an atom, molecule, ion, etc
• Reduction: Gain of electrons by an atom, molecule, ion, etc
• Oxidation-Reduction (REDOX) reactions involve gain (reduction) and loss (oxidation) of electrons
• Oxidizing Agent: Causes another species to be oxidized by accepting/taking electrons from it
• Reducing Agent: Causes another species to be reduced by donating electrons to it
• In a basic solution, use either OH- or H2O as the product to balance the reduction half reaction
• Under acidic conditions, use H2O as the product to balance the reduction half reaction
• Galvanic cell: a cell where a spontaneous chemical process produces electrical energy
• Electrolytic cell: a cell where electrical energy is used to bring about a non-spontaneous process
• In a galvanic cell, oxidation occurs at the anode and reduction at the cathode
• In a galvanic cell, if the anode is connected to the negative terminal of the voltmeter, the voltage reading is always positive
• The electron flow in a galvanic cell is from the anode to the cathode
• The anode is ALWAYS on the LEFT and cathode on the RIGHT
• "|" - indicates a junction between different phases, e.g., sol'n & metal, sol'n & gas or metal & compound
• "||" – indicates the salt bridge that connects the two solutions
• Standard cell potential (E°) is the difference between the standard reduction potentials of the two electrodes: E°(cell) = E°(cathode) – E°(anode)
• The species that is REDUCED at the cathode is the one with the most POSITIVE reduction potential
• The species that is OXIDISED at the anode is the one with the most NEGATIVE (least positive) reduction potential
• Metallurgy is a blend of chemistry, physics, and engineering focused on the production of metals
• Roasting is the process of heating a mineral in air to obtain the oxide