11. (12pts) for the redox reaction given below, ni(s) + 2 h(aq) + ni2+(aq) + h2(e) (show your work in detail) a) write oxidation and reduction half cell reactions b) write the electrochemical cell notation c) predict whether this reaction will be spontaneous. explain. d) calculategº 6 page

a) Anode:  

Cathode :

b)

c) As , the reaction is spontaneous.

d)

Explanation:

a) Here Ni undergoes oxidation by loss of electrons, thus act as anode. Hydrogen undergoes reduction by gain of electrons and thus act as cathode.

Anode:  

Cathode :

b) The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a slat bridge. Then the cathodic ion with its molar concentration is written and then the cathode.

c)

Where both are standard reduction potentials.

= +ve, reaction is spontaneous

= -ve, reaction is non spontaneous

= 0, reaction is in equilibrium

Thus as , the reaction is spontaneous.

d) The standard emf of a cell is related to Gibbs free energy by following relation:

= standard gibbs free energy

n= no of electrons gained or lost

F= faraday's constant

= standard emf

Thus value of Gibbs free energy is -48250 Joules.