Balance the following redox equation using the oxidation-number-change method. Describe each step you use to balance to reaction. HCL(aq) + Zn(s) --> ZnCl2(s) + H2(g)
Zn --> Zn²⁺ + 2e this is an oxidation reaction, since the oxidation number of Zn increases from 0 to +2 2H⁺ + 2e --> H₂ this is a reduction reaction, since the oxidation number of H decreases from +2 to 0. we can directly add the 2 equations as number of electrons are balanced, Zn + 2H⁺ ---> Zn²⁺ + H₂ we add 2 Cl⁻ ions to both sides of the equation, then the balanced redox reaction is,
