What mass of copper will be deposited by passing 2 faraday of electricity through a solution of Cu(II) salt?
1. 35.6 g
2. 63.5 g
3. 6.35 g
4. 3.56 g
In electrolysis of NaCl when Pt electrode is taken then H2 is liberated at cathode while with Hg cathode it forms sodium amalgam because :
1. Hg is more inert than Pt
2. More voltage is required to reduce H+ at Hg than at Pt
3. Na is dissolved in Hg while it does not dissolve in Pt
4. Concentration of H+ ions is larger when Pt electrode is taken.
The same amount of electricity was passed through two cells containing molten Al2O3 and molten NaCl. If 1.8 g of Al were liberated in one cell, the amount of Na liberated in the other cell is:
1. 4.6 g
2. 2.3 g
3. 6.4 g
4. 3.2 g
If mercury is used as cathode in the electrolysis of aqueous NaCl solution, the ions discharged at cathode are:
1. H+
2. Na+
3. OH-
4. Cl-
A gas X at 1 atm is bubbled through a solution containing a mixture of 1MY- and 1MZ- at 25C. If the reduction potential of Z > Y > X, then:
1. Y will oxidise X and not Z
2. Y will oxidise Z and not X
3. Y will oxidise both X and Z
4. Y will reduce both X and Z
The solution of CuSO4 in which copper rod is immersed is diluted to 10 times, the reduction electrode potential:
1. increases by 0.030 V
2. decreases by 0.030 V
3. increases by 0.059 V
4. decreases by 0.059 V
A solution containing one mole per litre each of Cu(NO3)2, AgNO3, Hg2(NO3)2 and Mg(NO3)2 is being electrolyzed by using inert electrodes. The values of standard electrode potentials in volt (reduction potentials) are,
Ag+ /Ag = 0.80 V, /2Hg = 0.79 V,
Cu2+/Cu = +0.34 V and Mg2+/Mg = -2.37 V
With increasing voltage, the sequence of deposition of metals on the cathode will be:
1. Ag, Hg, Cu, Mg
2. Mg, Cu, Hg, Ag
3. Ag, Hg, Cu
4. Cu, Hg, Ag
The highest electrical conductivity of the following aqueous solution is of:
1. 0.1 M Acetic acid
2. 0.1 M Chloroacetic acid
3. 0.1 M Fluoroacetic acid
4. 0.1 M Difluoroacetic acid
During an electrolysis experiment, if a 100 mA current is passed through a solution of AgNO3 for 30 minutes, how many coulombs of electricity will be consumed?
1. 108 C
2. 18000 C
3. 180 C
4. 3000 C
Standard reduction potentials at 25C of Li+/Li, Ba2+/Ba, Na+/Na and Mg2+/Mg are -3.05, -2.90, -2.71 and -2.37 V respectively. Which one of the following is the strongest oxidising agent ?
1. Mg2+
2. Ba2+
3. Na+
4. Li+