Electrochemical potential

Question 1

what are the 3 types of half cell

Answer 1

1. metal/metal ion
2. solution
3. Gas

Question 2

what is a metal/metal ion half cell made of

Answer 2

• electrode made of the metal
• dipped into a 1moldm⁻³ solution of the metal ions

Question 3

what is the solution half cell made of

Answer 3

• solution made of both oxidised and reduced form (1moldm⁻³)
• platinised electrode
• salt bridge

Question 4

what is the salt bridge made of

Answer 4

saturated potassium nitrate

Question 5

what are the conditions used for the gas half-cell

Answer 5

• 1moldm⁻³ solution
• platinised electrode
• 1atm, 298K

Question 6

what is connected to electrodes to provide a reading

Answer 6

high resistance voltsmeter

Question 7

what is the function of the salt bridge

Answer 7

allows ions to flow between the solution, therefore completing the circuit

Question 8

what are the half cells connected to

Answer 8

a standard hydrogen electrode

Question 9

what is a standard hydrogen electrode

Answer 9

hydrogen gas at
- 1atm
- solution of 1moldm⁻³ H⁺ ions
- platinised electrode

Question 10

which side is hydrogen electrode placed

Answer 10

left

Question 11

what does it mean if a + reading is given

Answer 11

half cell undergoes reduction
electrons flow left to right

Question 12

what does it mean if a - reading is given

Answer 12

half cell undergoes oxidation
electrons flow right to left