voltaic cell. ClO3^-(aq) + 6H^+(aq) + 6e^- → Cl^-(aq) + 3H2O(l)

The two half-reactions in a voltaic cell are

Zn(s) → Zn^2+(aq) + 2e^- (electrode = Zn)

ClO3^-(aq) + 6H^+(aq) + 6e^- → Cl^-(aq) + 3H2O(l) (electrode = Pt)

a) Indicate which reaction occurs at the anode

and which at the cathode.

b) Does the zinc electrode gain, lose, or retain

the same mass as the reaction proceeds?

c) Does the platinum electrode gain, lose, or retain

the same mass as the reaction proceeds?

d) Which electrode is positive?

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▶ Cell notation

Zn(s) | Zn^2+(aq) || H^+(aq), ClO3^-(aq), Cl^-(aq) | Pt(s)

Zn 산화 전극(anode) ↔ Pt 환원 전극(cathode)

anode = (–)극 ↔ cathode = (+)극

▶ The balanced equation for the overall redox reaction

3Zn(s) + ClO3^-(aq) + 6H^+(aq)

→ 3Zn^2+(aq) + Cl^-(aq) + 3H2O(l)

a) Indicate which reaction occurs at the anode

and which at the cathode.

---> The first reaction occurs at the anode

Zn(s) → Zn^2+(aq) + 2e^- (electrode = Zn)

and the second reaction at the cathode.

ClO3^-(aq) + 6H^+(aq) + 6e^- → Cl^-(aq) + 3H2O(l) (electrode = Pt)

b) Does the zinc electrode gain, lose, or retain

the same mass as the reaction proceeds?

---> The anode (Zn) is consumed in the cell reaction.

---> lose

c) Does the platinum electrode gain, lose, or retain

the same mass as the reaction proceeds?

---> retain

d) Which electrode is positive?

---> The cathode is positive.

[키워드] 볼타 전지 기준

a) Indicate which reaction occurs at the anode and which occurs at the cathode.

b) Which electrode is consumed (corroded) in the cell reaction?

c) Which electrode is positive?

d) Write the balanced equation for the overall redox reaction.