Rust

[Kenneth Dang 3I]

Can someone explain to me how water speeds up oxidation if it isn't involved in the oxidation equation?

[Henry Lewis 3F]

Remember that oxidation and reduction reactions typically act in pairs. While iron might be oxidizing, or releasing electrons, a substance has to receive those electrons to keep a reliable current. Water is reduced for iron to be oxidized. I would not say that water "speeds" up a reaction; you might be thinking of salts that add electrolytes. I think water is essential in order for the oxidation-reduction pair to occur.

[Jolene Robles 2H]

Waters speeds up oxidation even though it is not involved in the oxidation equation, because water can be seen as catalyst meaning it speeds up the reaction by increasing frequency collisions. It is able to create movement in reactant molecules which is why water is sometimes referenced as a "reactant like catalyst." For example water can be a catalyst is in the oxidation of alcohols such as ethanol (CH3CH2OH) to ethanal (CH3CHO).

[Averie Moore 2F]

Although it is not involved in the oxidation equation, water speeds up oxidation for several different reasons depending on the case. Water is polar so it can dissolve many different substances. Water can also ionize into H+, promoting the transfer of electrons (same applies for electrolysis). Water can also stabilize intermediates, preventing recombination and promoting further oxidation. The oxygen in water can also participate in redox processes directly or indirectly.