For the electrochemical cell, M | M+ || X- | X, (M+| M) = 0.44 V and (X | X-) = 0.33 V. From this data one can deduce that
M + X- M- + X- is the spontateous reaction.
M+ + X- M + X is the spontaneous reaction.
Ecell = 0.77 V
Ecell = -0.77V
Assertion : Magnesium is extracted by the electrolysis of fused mixture of MgCl2, NaCl and CaCl2.
Reason : Calcium chloride acts as a reducing agent.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion : Zinc displaces copper from copper sulphate solution.
Reason : The of zinc is= 0.76 V and that of copper is + 0.34 V.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
A.
If both assertion and reason are true and reason is the correct explanation of assertion.
Zinc metal is more reactive than the copper. Moreover, it is placed on the top of the reactivity series. This is why, zinc metal can displace copper from copper sulphate solution but copper cannot displace zinc from zinc sulphate solution. Copper being placed below zinc cannot displace it from zinc salts.
Which of the following does not conduct electricity ?
Fused NaCl
Solid NaCl
Brine solution
Copper
When a quantity of electricity is passed through CusO4 solution , 0.16 g of copper gets deposited .If the same quantity of electricity is passed through acidulated water , then the volume of H2 liberated at STP will be :
[Given : atomic weight of Cu = 64]
10 cm3
56 cm3
604 cm3
8.0 cm3
Which one of the following condition will increase the voltage of the cell represented by the equation ?
Cu (s) + 2Ag+ (aq) Cu2+ (aq) + 2Ag (s)
Increase in the dimension of Cu electrode
Increase in the dimension of Ag electrode
Increase in the concentration of Cu2+ ion
Increase in the concentration of Ag+ ions
Which of the following electrolyte will have maximum flocculation value for Fe(OH)3 sol ?
NaCl
Na2S
(NH4)3PO4
K2SO4
The time period to coat a metal surface of 80 cm2 with 5 x 10-3 cm thick layer of silver (density 1.05 g cm-3) with the passage of 3 A current through a silver nitrate solution is
115 sec
125 sec
135 sec
145 sec
Ni/Ni2+ [1.0 M] || Au3+ [1.0 M]/Au (where E° for Ni2+/Ni is -0.25 V E° for Au3+/Au is 0.150 V)
Whar is the emf of the cell ?
+ 0.4 V
- 1.75 V
+ 1.25 V
+ 1.75 V
The specific conductance of a N/ 10 KCl at 25°C is 0.0112 ohm-1cm-1.The resistance of cell containing solution at the same temperature was found to be 55 ohm. The cell constant will be
6.16 cm-1
0.616 cm-1
0.0616 cm-1
616 cm-1