In the reaction 2NH4++6NO3- → NO2 +N2 +2H2O the reducing agent is

Explanation

In a redox reaction, a reducing agent loses electrons and increases its oxidation state. Let's analyze each option to identify the species undergoing electron loss:NH4⁺:Initial oxidation state of N: +1 (in NH4⁺)Final oxidation state of N: +2 (in NO2)Since the oxidation state increases, NH4⁺ loses electrons and acts as the reducing agent.H⁺: H⁺ is a proton and doesn't have an oxidation state, so it's not involved in electron transfer.NO3⁻:Initial oxidation state of N: +5 (in NO3⁻)Final oxidation state of N: +2 (in NO2)The oxidation state decreases, indicating gain of electrons, so NO3⁻ is not the reducing agent.N2:N2 already has an oxidation state of 0, and its state remains unchanged in the reaction. It's not involved in electron transfer.Therefore, based on the changes in oxidation states, NH4⁺ is the species losing electrons and acting as the reducing agent.