What is the SHE? Sketch/describe this half-cell. What is the half-cell potential

Question

What is the SHE? Sketch/describe this half-cell. What is the half-cell potential? Consider the Cu(ll) | Cu and Zn(l) | Zn half-cell couples. Write the reaction that takes place spontaneously under standard state conditions. Which atom/ion is oxidized and which is reduced? Which couple is at the anode and which is at the cathode? Use the table of standard half-cell potentials to determine Edegrees for the reaction. Sketch the electrochemical cell with labels for each important feature. Explain how the cell potential changes as the concentration decreases.

Explanation / Answer

we know that

Cu acts as cathode and zinc is the anode

the reaction is

Cu+2 + 2Zn (s) ---> Cu (s) + 2Zn+

the reaction quotient is given by

Q = [Zn+]^2 / [Cu+2]

now

according to nernst equation

E= Eo - ( 0.059/n) log Q

in this reaction

n = 2 as two electrons are transferred

so

E= Eo - ( 0.059/2) log [Zn+]^2 / [Cu+2]

E = Eo - 0.0295 log [Zn+2] / [Cu+2]

so

from the above equation

we can see that

As [Zn+] increases cell potential decreases

As [Zn+2] decreases , cell potential increases

and

As [Cu+2] increases , cell potential increases

As [Cu+2[ decreases , cell potential decreases

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.