In the electrochemical cell:

Zn|ZnSO₄(0.01 M) || CuSO₄(1.0M),Cu, the emf of this Daniel cell is E₁. When the concentration of ZnSO₄ is changed to 1.0 M and that of CuSO₄ is changed to 0.01 M, the emf changes to E₂. The relationship between E₁ and E₂ is : 
( Given, $\frac{RT}{\mathrm{F }}$= 0.059)

1. E₁ = E₂

2. E₁ < E₂

3. E₁ > E₂

4. E₂ = 0 $\ne$E₁

Zinc can be coated on iron to produce galvanised iron but the reverse is not possible. It is because

(1) zinc is lighter than iron

(2) zinc has lower melting point than iron

(3) zinc has lower negative electrode potential than iron

(4) zinc has higher negative electrode potential than iron

The pressure of H₂ required to make the potential of H₂ - electrode zero in pure water at 298 K is: