A reducing agent is a substance that causes another substance to gain electrons, thereby reducing its oxidation state. It is itself oxidized in the process.
In a redox equation, the reducing agent transfers electrons to the oxidizing agent, causing a reduction reaction. This results in a decrease in the oxidation state of the oxidizing agent and an increase in the oxidation state of the reducing agent.
The reducing agent is responsible for initiating the reduction reaction by donating electrons to the oxidizing agent. Without a reducing agent, the redox reaction cannot occur.
No, not all substances can act as reducing agents. A substance must have a lower electronegativity than the oxidizing agent in order to donate electrons and cause a reduction reaction to occur.
The reducing agent in a redox equation can be identified by looking at the changes in oxidation states of the reactants and products. The substance that undergoes a decrease in oxidation state is the reducing agent.