Question

decide whether each chemical reaction in the table below is an oxidation - reduction (
edox\) reaction. if the reaction is a redox of the reducing agent and the formula of the oxidizing agent.

2n₂(g)+5o₂(g)→2n₂o₅(g)

s₈(s)+4pb(s)→4pbs₂(s)

cuso₄(aq)+zn(s)→znso₄(aq)+cu(s)

Explanation:

Step1: Determine oxidation states

• For \(2N_2(g)+5O_2(g)\to2N_2O_5(g)\):
• In \(N_2\), \(N\) has an oxidation state of \(0\). In \(N_2O_5\), \(N\) has an oxidation state of \(+5\) (since \(O\) is \(- 2\) and for \(N_2O_5\): \(2x+5\times(-2)=0\), \(2x = 10\), \(x = + 5\)).
• In \(O_2\), \(O\) has an oxidation state of \(0\). In \(N_2O_5\), \(O\) has an oxidation state of \(-2\).
• Since oxidation states change (\(N\) is oxidized from \(0\) to \(+5\), \(O\) is reduced from \(0\) to \(-2\)), it is a redox reaction.
• The reducing agent is \(N_2\) (it donates electrons and gets oxidized).
• The oxidizing agent is \(O_2\) (it accepts electrons and gets reduced).

Step2: For \(S_8(s)+4Pb(s)\to4PbS_2(s)\):

• In \(S_8\), \(S\) has an oxidation state of \(0\). In \(PbS_2\), \(S\) has an oxidation state of \(-1\) (since \(Pb\) is \(+2\) and for \(PbS_2\): \(+2 + 2y=0\), \(2y=-2\), \(y=-1\)).
• In \(Pb\), \(Pb\) has an oxidation state of \(0\). In \(PbS_2\), \(Pb\) has an oxidation state of \(+2\).
• Since oxidation states change (\(Pb\) is oxidized from \(0\) to \(+2\), \(S\) is reduced from \(0\) to \(-1\)), it is a redox reaction.
• The reducing agent is \(Pb\) (it donates electrons and gets oxidized).
• The oxidizing agent is \(S_8\) (it accepts electrons and gets reduced).

Step3: For \(CuSO_4(aq)+Zn(s)\to ZnSO_4(aq)+Cu(s)\):

• In \(CuSO_4\), \(Cu\) has an oxidation state of \(+2\). In \(Cu\), \(Cu\) has an oxidation state of \(0\).
• In \(Zn\), \(Zn\) has an oxidation state of \(0\). In \(ZnSO_4\), \(Zn\) has an oxidation state of \(+2\).
• Since oxidation states change (\(Zn\) is oxidized from \(0\) to \(+2\), \(Cu\) is reduced from \(+2\) to \(0\)), it is a redox reaction.
• The reducing agent is \(Zn\) (it donates electrons and gets oxidized).
• The oxidizing agent is \(CuSO_4\) (it accepts electrons and gets reduced).

Answer:

For \(2N_2(g)+5O_2(g)\to2N_2O_5(g)\): redox reaction? yes; reducing agent: \(N_2\); oxidizing agent: \(O_2\)
For \(S_8(s)+4Pb(s)\to4PbS_2(s)\): redox reaction? yes; reducing agent: \(Pb\); oxidizing agent: \(S_8\)
For \(CuSO_4(aq)+Zn(s)\to ZnSO_4(aq)+Cu(s)\): redox reaction? yes; reducing agent: \(Zn\); oxidizing agent: \(CuSO_4\)