Class 11th

The given redox reaction can be depicted as

Zn (s) + 2Ag⁺ (aq) → Zn²⁺ (aq) + 2Ag (s)
Since Zn gets oxidised to Zn²⁺ ions, and Ag⁺ gets reduced to Ag metal, therefore,

Oxidation occurs at the zinc electrode and reduction occurs at the silver electrode. Thus, galvanic cell corresponding to the above redox reaction may be depicted as:

Zn|Zn²⁺ (aq) | Ag⁺ (aq) | Ag

(i) Zinc electrode is negatively charged because oxidation occurs at the zinc electrode (i.e. electrons accumlulate on the zinc electrode)

(ii) The ions carry current. The electrons flow from Zn to Ag electrode while the current flows from Ag to Zn electrode.

(iii) Reaction occurring at each electrode are:

Zn (s) → Zn²⁺ (aq) + 2e^-

Ag⁺ (aq) + e^- → Ag (s)

5.36.  Avogadro law states that equal volumes of all gases under same conditions of temperature and pressure contain equal number of molecules.

Dalton's law of partial pressure states that total pressure exerted by a mixture of non-reacting gases is equal to the sum of partial pressures exerted by them.

Boyle's law states that under isothermal condition, pressure of a fixed amount of a gas is inversely proportional to its volume.

Charles' law is a relationship between volume and absolute temperature under isobaric condition. Itstates that volume of a fixed amount of gas is directly proportional to its absolute temperature (V? T).

(i) An aqueous solution of AgNO₃?  with silver electrodes.
At cathode: Silver ions have lower discharge potential than hydrogen ions. Hence, silver ions will be deposited in preference to hydrogen ions.

At anode: Silver anode will dissolve to form silver ions in the solution.
Ag → Ag⁺ + e⁻

(ii) An aqueous solution of AgNO_3?  with platinum electrodes.

At cathode: Silver ions have lower discharge potential than hydrogen ions. Hence, silver ions will be deposited in preference to hydrogen ions.

At anode: Hydroxide ions having lower discharge potential will be discharged in preference to nitrate ions. Hydroxide ions will decompose to give oxygen.
4OH⁻ (aq) → 2H₂? O (l) + O₂? (g) + 4e⁻

(iii) A dilute solution of H₂? SO₄?  with platinum electrodes.

At cathode: 2H⁺ + 2e⁻ → H₂? (g)

At anode: Hydroxide ions having lower discharge potential will be discharged in preference to sulphate ions. Hydroxide ions will decompose to give oxygen.
4OH⁻ (aq) → 2H₂? O (l) + O₂? (g) + 4e⁻

(iv) An aqueous solution of CuCl₂?  with platinum electrodes

At cathode: Cupric ions will be reduced in preference to protons
Cu²⁺ + 2e⁻ → Cu

At anode: Chloride ions will be oxidized in preference to hydroxide ions
2Cl⁻ → Cl₂? + 2e⁻