The metals among the following that can be extracted electrolytically is -
1. K
2. Na
3. Al
4. All of the above
Rusting of iron is envisaged as setting up of an electrochemical cell because:
1. Oxidation of iron takes place during rusting.
2. Reduction of iron takes place.
3. Iron shows disproportionation reaction.
4. Oxygen is getting oxidised.
The cell in which the following reactions occurs:
2Fe3+(aq)+2I-(aq)→2Fe2+(aq)+I2(s) has \(E_{cell}^{o}\)= 0.236 V at 298 K.
The standard Gibbs energy of the cell reaction is −45.54 kJ mol−1 . The value of equilibrium constant of the cell reaction is
1. 10.27 × 109
2. 9.57 × 107
3. 12.17 × 108
4. 7.17 × 106
The number of electrons flow through the wire when a current of 0.5 ampere flows through a metallic wire for 2 hours, is-
1. \(6.25×10^{22}\)
2. \(2.25×10^{22}\)
3 \(8.25×10^{22}\)
4. \(4.25×10^{22}\)
The molar conductivity of 0.025 mol L−1 methanoic acid is 46.1 S cm2 mol−1.
The dissociation constant of methanoic acid is-
Given λ°(H+)= 349.6 S cm2 mol−1 and λ°(HCOO−) = 54.6 S cm2 mol
1. \(1.27×10^{-4}mol ~L^{−1}\)
2. \(5.17×10^{-5}mol ~L^{−1}\)
3. \(3.67×10^{-4}mol ~L^{−1}\)
4. \(4.87×10^{-5}mol ~L^{−1}\)
Assertion (A): | The conductivity of a solution decreases with dilution. |
Reason (R): | Conductivity of a solution depends on the number of ions and the number of ions decreases when the solution is diluted. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |
The cell in which the following reactions occurs:
2Fe3+(aq)+2I-(aq)→2Fe2+(aq)+I2(s) has \(E_{cell}^{o}\)= 0.236 V at 298 K.
The standard Gibbs energy of the cell reaction is -
1. 41.14 kJ mol−1
2. 45.54 kJ mol−1
3. −49.94 kJ mol−1
4. −45.54 kJ mol−1
The emf of the cell in which the following reaction takes place is:
Ni(s)+2Ag+(0.002 M) →Ni2+(0.160 M) + 2Ag(s)
( Given that \(E_{cell}^{o}\)= 1.05 V)
1. Ecell= 9.14 V
2. Ecell= 0.0914 V
3. Ecell= 0.00914 V
4. Ecell= 0.914 V