Electrolysis and Electrolytes

Q. A 4.0 M aqueous solution of NaCl is prepared and 500 mL of this solution is electrolyzed. This leads to the evolution of chlorine gas at one of the electrodes (atomic mass of Na is 23 and Hg is 200)

1 F = 96500 C.

The total charge (coulomb) required for complete electrolysis is

1. 24125
2. 48250
3. 96500
4. 193000

Q.

Electrolytes when dissolved in water dissociates into ions because

[CPMT 1974, 78; MNR1983]

1. They are unstable

2. The force of repulsion increases

3. The forces of electrostatic attraction are broken down by water

4. The water dissolves it

Q.

State two applications of electrolysis.

Q.

Which one of the following metals could not be obtained on electrolysis of aqueous solution of its salts

[IIT 1990]

1. Ag

2. Mg

3. Cr

4. Cu

Q.

(iii) Write two applications of electrolysis in which electrode diminishes in mass?

Q.

Electric current is passed through an aqueous solution of the following. Which one shall decompose

[NCERT 1972]

1. Urea

2. Glucose

3. AgNO₃

4. Ethyl alcohol

Q.

Which of the following will not conduct electricity in aqueous solution

[AMU 1982, 83]

1. Copper sulphate

2. Sugar

3. Common salt

4. None of these

Q.

Which solution (Acid or Base) contains H+ions less than OH- ions ?

Q. What would happen if the electrodes were put in a saturated solution of glucose which is dissolved in water?

1. Light bulb would glow
2. Light bulb would remain dark
3. Apparatus would combust
4. Glucose molecules would dissociate
5. None of the above

Q.

Given that $2C{l}^{-}\to C{l}_2+2e^{-},E^{\circ }=-1.36V;$
$H_{2}O\to 2H^{+}+\frac{1}{2}{O}_2+2e^{-},E^{\circ }=-1.23V.$ On electrolysing 1M NaCl solution with inert electrodes, which of the following is correct regarding liberation of electrolytic products ?

1. Cathode : Na and $H_2$

2. Cathode : $Na,O_2$

3. Anode : $C{l}_2$

4. Anode : $O_2$

Q. The process of electrolysis involves

1. Decomposition of the electrolyte
2. Decomposition of the cathode
3. Decomposition of the anode
4. Breakdown of the cell

Q. $16.8$ litre gas containing $H_2$ and $O_2$ is formed at $NTP$ on electrolysis of water. What should be the weight of electrolysed water?

1. $5g$
2. $9g$
3. $10g$
4. $12g$

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> When and where is the first soap believed to have been made?

Q.

Electrolysis is carried out in three cells : (A) - 1.0$MCuS{O}_4,$ Pt electrodes; (B) - 1.0 $MCuS{O}_4,$, Copper electrode; (C) - 1.0 $MKCl$, Pt electrodes. If the volume of electrolytic solution is maintained constant in each of the cells, which is correct set of pH changes in (A), (B) and (C) cells respectively?

1. increase in all the three

2. decrease in all the three

3. increase, constant, increase

4. decrease, constant, increase

Q. A 4.0 molar aqueous solution of NaCI is prepared and 500 mL of this solution is electrolysed.This leads to the evolution of chlorine gas at one of the electrodes. If the cathode is a Hg electrode, the maximum weight (g) of amalgam formed from this solution is: (atomic mass : Na =23, Hg = 200)

1. 200
2. 225
3. 446
4. 400