Question

Calculate the standard cell potential for each of the following electrochemical cells.Standard Electrode Potentials at 25 ∘CReduction Half-ReactionE∘(V)Cd2+(aq)+2e−→Cd(s)-0.40Mg2+(aq)+2e−→Mg(s)-2.372H+(aq)+2e−→H2(g)0Zn2+(aq)+2e−→Zn(s)-0.76Cd2+(aq)+Mg(s)→Cd(s)+Mg2+(aq)

Answer 1

Explanation:

We have to fhnd the standard cell potencial for this electrochemical cell:have to fi

Cd²⁺ (aq) + Mg (s) ----> Cd (s) + Mg²⁺ (aq)

We are given these electrode potentials at 25 °C.

Cd²⁺ (aq) + 2 e- ----> Cd (s) E∘(V) = - 0.40

Mg²⁺ (aq) + 2 e− ----> Mg (s) E∘(V) - 2.37

In our reaction, Cd is being reduced from i ou to solid Cd. Solid Mg is being oxidized from solid Mg to Mgd . In electrochemistry, the anode is where oxidation occurs and the cathode is where reduction occurs.

Cd²⁺ (aq) + 2 e- ----> Cd (s) Reduction = Cathode

Mg (s) ----> Mg²⁺ (aq) + 2 e− Oxidation = Anode

The standard cell potential of an electrochemicalectro will be hdard to reduction potential of the cathode minus that of the anode.²s) Cd (s) ²⁺

E°cell = E°cathode - E°anode

E°cell = -0.40 V - (- 2.37 V)

E°cell = 1.97 V

Answer: the standard cell potential of the electrochemical cell is 1.97 V.