Silver nitrate and magnesium reaction. High-speed footage of water (H2O) being splashed on a mixture of silver nitrate (AgNO3) and magnesium (Mg), resulting in an explosive reaction. The addition of water increases contact between the reactants and initiates the reaction, causing an exothermic displacement of the silver by the more reactive magnesium. The products of the reaction are magnesium nitrate (Mg[NO3]2) and silver metal (Ag). Part of the flash is caused by the excess magnesium igniting.