you are given the reaction cu + hno₃ → cu(no₃)₂ + no + h₂o. which pair of half - reactions represents the…

you are given the reaction cu + hno₃ → cu(no₃)₂ + no + h₂o. which pair of half - reactions represents the balanced half - reactions for the reaction? o 3cu → 3cu²⁺ + 6e⁻ 2n⁵⁺ + 6e⁻ → 2n²⁺ o cu → cu²⁺ + 2e⁻ n⁵⁺ + 3e⁻ → n²⁺ o 2cu → 2cu²⁺ + 6e⁻ 3n⁵⁺ + 6e⁻ → 3n²⁺ done

you are given the reaction cu + hno₃ → cu(no₃)₂ + no + h₂o. which pair of half - reactions represents the balanced half - reactions for the reaction? o 3cu → 3cu²⁺ + 6e⁻ 2n⁵⁺ + 6e⁻ → 2n²⁺ o cu → cu²⁺ + 2e⁻ n⁵⁺ + 3e⁻ → n²⁺ o 2cu → 2cu²⁺ + 6e⁻ 3n⁵⁺ + 6e⁻ → 3n²⁺ done

Answer

Explanation:

Step1: Analyze oxidation of Cu

Copper (Cu) goes from an oxidation - state of 0 in elemental Cu to + 2 in $Cu(NO_3)_2$. The half - reaction for the oxidation of Cu is $Cu\rightarrow Cu^{2 +}+2e^-$. To balance the overall reaction in terms of electrons transferred, we need to consider the reduction half - reaction.

Step2: Analyze reduction of N in $HNO_3$

Nitrogen in $HNO_3$ has an oxidation state of + 5 and in NO it has an oxidation state of + 2. The reduction half - reaction for nitrogen is $N^{5+}+3e^-\rightarrow N^{2 +}$. To balance the electrons in the overall redox reaction, we multiply the oxidation half - reaction by 3 and the reduction half - reaction by 2 so that the number of electrons lost in oxidation equals the number of electrons gained in reduction. The balanced oxidation half - reaction is $3Cu\rightarrow3Cu^{2 +}+6e^-$ and the balanced reduction half - reaction is $2N^{5+}+6e^-\rightarrow2N^{2 +}$.

Answer:

$3Cu\rightarrow3Cu^{2 +}+6e^-$ $2N^{5+}+6e^-\rightarrow2N^{2 +}$