The reaction taking place at anode when an aqueous solution of CuSO4 is electrolysed using inert Pt electrode:
1. 2 S2 + 2e
2. Cu2+ + 2e Cu
3. 2H2O O2 + 4H+ + 4e
4. 2H+ +2e H2
When a lead storage battery is discharged, then:
1. SO2 is evolved.
2. Lead is formed.
3. Lead sulphate is consumed.
4. Sulphuric acid is consumed.
Each of the three metals X, Y and Z were put in turn into aqueous solution of the other two.
Which observation is probably incorrect?
1. Y + Salt of X = No action observed
2. Y + Salt of Z = Z + Salt of Y
3. Z + Salt of X = X + Salt of Z
4. Z + Salt of Y = No action observed
The change in reduction potential of a hydrogen electrode when its solution initialy at pH = 0 is neutralised to pH = 7, is a/an-
1. | Increase by 0.059 V | 2. | Decrease by 0.059 V |
3. | Increase by 0.41 V | 4. | Decrease by 0.41 V |
A depolariser used in dry cell batteries is:
1. Ammonium chloride
2. Manganese dioxide
3. Potassium hydroxide
4. Sodium phosphate
The standard reduction potentials of Cu2+/Cu and Cu2+/Cu+ are 0.337 and 0.153V respectively. The standard electrode potential of Cu+/Cu half cell is:
1. 0.184V
2. 0.827V
3. 0.521V
4. 0.490V
The cell reaction for the given cell is spontaneous if:
Ptcl2|cl-(1M)||Cl-(1M)|PtCl2
1. P1 > P2
2. P1 < P2
3. P1 = P2
4. P1 = 1 atm
The molar conductances of Ba2+ and Cl- 127 and 76Ω-1 cm-1 mol-1 respectively at infinite dilution. The equivalent conductance of BaCl2 at infinite dilution will be
1. 139.52
2. 203
3. 279
4. 101.5
The electric charge for electrode deposition of 1g equivalent of a substance is:
1. 1 ampere per second
2. 96,500 coulomb per second
3. 1 ampere for 1 hour
4. charge on 1 mole of electrons
The ratio of masses of hydrogen and magnesium deposited by the same amount of electricity from H2SO4 and MgSO4 in aqueous solution are:
1. 1:8
2. 1:12
3. 1:16
4. None of the above