Magnesium and graphite: an electricity experiment #science #chemistry #cathode #anode #physics

In this experiment, we dissolve 8-10g of table salt in 100 ml of water, then place magnesium and graphite plates in the solution. The magnesium acts as the active anode and the graphite as the inert cathode. When the plates are connected, a galvanic cell is formed. The magnesium oxidizes at the anode (Mg → Mg²⁺ + 2e⁻), while water is reduced at the cathode, producing hydrogen gas (2H₂O + 2e⁻ → H₂O + 2OH⁻). Hydrogen evolution can also be observed on the magnesium plate due to a parallel reaction between magnesium and water (Mg + 2H₂O → Mg(OH)₂ + H₂). The salt serves as an electrolyte, conducting electric current and facilitating charge transfer between the electrodes, thereby completing the circuit.