Cell conventions

Question 1

What does a vertical solid line indicate?

Answer 1

• phase boundary
• e.g. between solid and solution

Question 2

What does a double vertical line show?

Answer 2

a salt bridge

Question 3

Where is the species with the highest oxidation state written?

Answer 3

next to salt bridge

Question 4

what is the equation for emf when using cell representation?

Answer 4

• emf = E^ϴ (r) - E^ϴ (l)
• polarity of the right electrode is always given

Question 5

What is the convention for the standard hydrogen electrode?

Answer 5

• Pt I H₂(g) I 2H⁺ (aq) II
  
  • boundary between Pt and H2
  • shows that hydrogen flowing over platinum
• always on left hand side
  
  • sign of the voltage quoted always gives you the sign of the metal electrode