Four successive members of the first-row transition elements are listed below with atomic numbers. Which one of them is expected to have the highest   value?

• Cr (Z =24)

• Mn(Z =25)

• Fe (Z = 26)

• Fe (Z = 26)

How many litres of water must be added to 1 L to an aqueous solution of HCl with a pH of 1 create an aqueous solution with PH of 2?

• 0.1 L

• 0.9 L 

• 2.0 L 

• 2.0 L 

The reduction potential of hydrogen half-cell will be negative if 

• p(H₂) = 1 atm and [H⁺] = 2.0 M

• p(H₂) = 1 atm and [H⁺] = 1.0 M

• p(H₂) = 2 atm and [H⁺] = 1.0 M

• p(H₂) = 2 atm and [H⁺] = 1.0 M

The degree of dissociation (α) of a weak electrolyte ,A_xB_y is related to van't Hoff factor (i) by the expression

The Gibbs energy for the decomposition of Al₂O₃ at 500°C is as follows

The potential difference needed for electrolytic reduction of Al₂O₃ at 500°C is at least

• 4.5 V

• 3.0 V

• 2.5 V

• 2.5 V

346.

Given,


Among the following, the strongest reducing agent is

• Cr

• Mn²⁺

• Cr³⁺

• Cr³⁺

Given:  The value of standard electrode potential for the change  will be

• -0.072

• 0.385 V

• 0.770 V

• 0.770 V

On the basis of the following thermochemical data: (∆f G° H(aq)+=0)
H₂O(l) → H⁺(aq) + OH^–(aq); ∆H =57.32kJ
H₂(g) + 1/2O₂(g) → H₂O(l); ∆H = –286.20 kJ
The value of enthalpy of formation of OH^–ion at 25°C is

•  –22.88 kJ

• –228.88 kJ

• +228.88 kJ

• +228.88 kJ

• 0.26

• 0.399

• 0-399

• 0-399

The cell, Zn|Zn²⁺ (1M)|| Cu²⁺ (1M|Cu(Eocell = 1.10 V), was allowed to be completely discharged at 298 K. THe relative concentration of Zn²⁺ to Cu²⁺ 

• antilog (24.08)

• 37.3

• 10^37.3

• 10^37.3