Standard hydorgen electrode

Question 1

What is the reference electrode?

Answer 1

• unable to measure the absolute voltage between metal and solution
  
  • it is enough to compare voltage to one another
• we need to compare
  
  • position of equilibrium
  • how readily the metal sheds electrons

Question 2

What is the solution in the standard hydrogen electrode?

Answer 2

solution of H+(aq) ions

Question 3

How is electrical contact made? Why is it done this way?

Answer 3

• unreactive platinum metal inserted
• since hydrogen doesn’t conduct

Question 4

Describe the plantinum metal?

Answer 4

• coated with finely divided platinum to increase SA and allow the reaction to proceed rapidly

Question 5

What is the condition for the electrode?

Answer 5

• standard condition
  
  • 100kPa
  • 298k
• [H+(aq)] = 1.00 mol dm^-3

Question 6

What is the potential of the standard hydrogen electode?

Answer 6

• defined as zero

Question 7

What happens when the SHE is conencted to another electrode?

Answer 7

• the measured emf is the electrode potential of the cell

Question 8

When are electodes given the symbol E^ϴ

Answer 8

• standard condition
• 298k, 100kPa, [metal ions] = 1.00 mol dm^-3

Question 9

The more -ve the value of E^ϴ means what?

Answer 9

• better at releasing electrons
• better reducing agents
• (than hydrogen)
• eqm more to left
• greater amount of negativeness

Question 10

Define the standard electrode potential?

Answer 10

• emf measured when a metal / metal ion electrode is coupled to a hydrogen electrode under standard conditions is known as the standard electrode potential of that metal / metal ion combination