IGNOU MCH 4 2018 - Given the following reaction half reaction: Cd2+ + 2e ® Cd&nbs

Question

Given the following reaction half reaction:

Cd2+ + 2e ® Cd E° = - 0.403 V

Pb2+ + 2e-®Pb E° = - 0.126 V

where [Cd2+] = 0.020 M and [Pb2+] = 0.200 M

construct a galvanic cell using half cell reactions and find

i) Which half cell –reaction is the cathode?

ii) Write the cell reaction.

iii) Calculate $E_{cell}^{\circ}$ of this galvanic cell.

iv) Calculate Ecell of this galvanic cell

v) Calculate equilibrium constant using E°cell potentials of this galvanic cell based on the construction of ions.

06 Apr 2018

Answer :

Word Count : 389

The first step is to determine the cell reaction and total cell potential.

In order for the cell to be galvanic, E⁰cell > 0.

For this reaction to be galvanic, the cadmium reaction must be the oxidation reaction. Cd → Cd²+ + 2 e- E⁰ = +0.403 V
Pb²+ + 2 e- → Pb E⁰ = -0.126 V

The total cell reaction is:

Pb²+(aq) + Cd(s) → Cd²+(aq) + Pb(s)

and E⁰cell = 0.403 V + -0.126 V = 0.277 V

The Nernst equation is:

Ecell = E⁰cell - (RT/nF) x lnQ

_______ __________ _________ ________ _________ ___ _________.
_______ _______ ___ ___ ________ ____ _____ ________ _________ __________ ____.
_______ _________ ___ ____ __________ _____ _____ ______ __________.
_____ _______ _________ ____ ________ _______ ____ _______ ____ _________.
________ __________ __________ _______ ______ ________ _________.
________ ____ ______ ___ __________ __________ _________ _________ _______ _______ ___.
____ _____ _____ ________ __________ ___ ________ __________ __________ ______ _________.
________ _____ ____ _____ ____ _________ _______.
_________ _______ __________ ___ __________ _________ _________ __________.
_____ ___ __________ ________ _______ ________ _________.
___ ____ _______ ______ ______ _______.
_____ ______ _____ ____ ______ _______ _______.
_______ ______ _________ ____ ___ _____ __________ ______ _____ ___.
__________ ____ ____ ______ ___ ________ __________ __________.
_________ ____ ________ _______ ________ __________ _______.
_________ __________ _________ _______ _________ ________ ______ ____ __________ _________ __________.
___ ___ __________ __________ ___.
__________ __________ _______ ________ __________ ______ _______.
________ ___ __________ ________ __________ _________ ______ _____ __________ _______ ______.
___ ____ ____ ___ _________ __________ ___ _________ _________.
__________ _________ ________ _______ _______ _____.
________ __________ ________ ___ ___ ________ _________.
___ _________ _______ _______ ______ ___ ________.
___ _____ ______ ________ _________.
________ __________ ________ ___ __________ _______ ___ ___.
_______ ____ ____ ________ ______ _______ ______ _____ ______ _________.
___ __________ _________ ______ _____ _____ _______ ___ _____ _________.
___ ________ _____ __________ _____ ________ ________ _____ _______.
__________ ______ _______ ____ ________ ________ ____ _______ _________.
__________ ________ ____ __________ _______ ______ ______ ________ _________ ___.
___ _________ _______ ____ ________ ______ _________ _________ ____ _____.
____ ___ ____ __________ ___ _______ _______ ______.
_________ _______ __________ ______.

IGNOU ACADEMY

Your IGNOU journey, made easier.

Solved Assignments
Study Notes
Guess Papers
Question Papers

Call Us WhatsApp

STUDY • PREPARE • SUCCEED

Skip in 10