Question

PLEASE ANSWER ALL

4. The cell potential for the unbalanced chemical reaction: Hg2 2+(aq) + NO3 - (aq) + H+ (aq) → Hg2+(aq) + HNO2(aq) is measured under standard conditions and found to be + 0.02 V at 25C.

a) What substance (not just the element) is oxidized in the cell?

b) What substance (not just the element) is reduced in the cell?

c) Write the half-reaction that occurs in the anode compartment.

d) Write the half-reaction that occurs in the cathode compartment.

e) Use the half-reaction method to balance the cell reaction.

f) Write the cell notation for this Voltaic cell.

g) Draw a diagram of the electrochemical cell, labeling electrodes with their charges, show the direction of electron flow in the circuit, show the directions of the cations and anions from the salt bridge. Indicate the ions and molecules present in the anode compartment and the cathode compartment. (You many omit writing water molecules.) Label what is being used as the electrodes in each compartment.

5. Referring to the electrochemical cell in the previous problem.

a) Write the cell notation (line diagram) for the electrochemical cell.

b) Calculate the value of G for this cell reaction.

c) Calculate the equilibrium constant for this reaction at 25C.

d) Determine the cell potential at pH = 2.00, [Hg2 2+] = [NO3 - ] = [Hg2+] = [HNO2] = 0.10 M. Under these conditions in which direction is the cell reaction spontaneous at 25C?

Answer 1

Oxidation- oxidation no. Increases

Reduction - oxidation no.decreases