The pressure of H 2 required to make the potential of hydrogen electrode zero in pure water at 298 K is:

The pressure of H2 required to make the potential of hydrogen electrode zero in pure water at 298 K is:
  1. 10-14 atm
  2. 10-12 atm
  3. 10-10 atm
  4. 10-4 atm

Solution

Pt,H2gH+ Hydrogen electrode EH2/H+o=0.0 Volt

H2g→2Haq++2e-

H+=10-7 M at 25oC (for Pure water)

E=-0.05912log⁡H+2PH2

E=0=log⁡H+PH2=0

∴ H + 2 = P H 2 = 10 −7 2

∴PH2=10-14 atm

Asked in: MHT CET Full Test 12

Practice more Electrochemistry questions on Aicharya