Electrode Potentials

Question 1

What are the conditions for the standard electrode potential values?

Answer 1

298K
100kPa
1.00 moldm^-3

Question 2

What happens on the RHS of the 1/2 cell and what metal goes on the RHS?

Answer 2

Reduction
more +ve metal

Question 3

What happens on the LHS of the 1/2 cell and what metal goes on the LHS?

Answer 3

Oxidation
More -ve

Question 4

What do you use for the salt bridge? Why?

Answer 4

KNO3 (aq) - inert & conductor (has mobile ions)

Question 5

Outline how you would draw a conventional cell representation

Answer 5

ROOR
LHS then RHS separated by || = salt bridge
If the metals are different states separate with | - if both (aq) separate with ,

Question 6

What do you do with both equations of the cell?

Answer 6

Combine to make redox - ensure e- cancel out

Question 7

Outline the equation (with units) for the standard cell potential (emf)

Answer 7

emf (V) = (more +ve) - (more -ve)

Question 8

What do you use if both the metals on one side are aqueous?

Answer 8

Make the electrode solid Platinum

Question 9

How do you find the electrode potential values?

Answer 9

Connect 1/2 cell to the
Standard
Hydrogen
Electrode
at 0V

Question 10

What side do you set the S.H.E on?

Answer 10

LHS always

Question 10

How do you collect the H2 for the S.H.E?

Answer 10

Use a glass jacket

Question 11

Why does the S.H.E not have to be recharged?

Answer 11

H2 is constantly supplied

Question 12

Why do electrons flow from right to left/ left to right sometimes?

Answer 12

The concentration of one solution may be higher than another

Question 13

Why does the redox reaction between Cl and H2O not occur without light?

Answer 13

Ea is high & UV provides energy

Question 14

What is the model answer for questions that say “Use data from the table to explain why (X) can oxidise/redox/react with (Y)”?

Answer 14

(X) has a higher potential than (Y)