Balance each redox reaction occurring in acidic aqueous solution. c. NO₃^–(aq) + Sn²⁺(aq) → Sn⁴⁺(aq) + NO(g)

Verified step by step guidance

1. Identify the oxidation states of each element in the reactants and products. For NO3-, nitrogen is +5 and oxygen is -2. For Sn2+, tin is +2. In the products, for Sn4+, tin is +4, and for NO, nitrogen is +2.
2. Determine the changes in oxidation states to identify which elements are oxidized and which are reduced. Tin (Sn) is oxidized as its oxidation state increases from +2 to +4. Nitrogen (N) is reduced as its oxidation state decreases from +5 to +2.
3. Write the half-reactions for both oxidation and reduction. For oxidation: Sn2+ -> Sn4+ + 2e-. For reduction: NO3- + 4H+ + 3e- -> NO + 2H2O.
4. Balance the electrons in the half-reactions by multiplying the half-reactions by appropriate factors so that the number of electrons gained in the reduction half-reaction equals the number of electrons lost in the oxidation half-reaction. Multiply the oxidation half-reaction by 3 and the reduction half-reaction by 2.
5. Add the balanced half-reactions together and simplify to get the overall balanced equation in acidic solution: 3Sn2+ + 2NO3- + 8H+ -> 3Sn4+ + 2NO + 4H2O.

Key Concepts

Redox Reactions

Redox reactions, or reduction-oxidation reactions, involve the transfer of electrons between two species. In these reactions, one species is oxidized (loses electrons) while another is reduced (gains electrons). Understanding the oxidation states of the elements involved is crucial for identifying which species undergo these changes.

Balancing Redox Reactions

Balancing redox reactions requires ensuring that both mass and charge are conserved. This often involves separating the reaction into half-reactions: one for oxidation and one for reduction. In acidic solutions, hydrogen ions (H+) and water (H2O) are typically added to balance the equation, along with electrons to balance the charge.

Acidic Aqueous Solutions

In acidic aqueous solutions, the presence of H+ ions influences the behavior of the reactants and products. The pH level can affect the solubility and reactivity of certain species. When balancing redox reactions in such environments, it is essential to account for these ions, as they can participate in the reaction and affect the overall stoichiometry.