Electrolysis and Electrolytes

Q. The volume of gases evolved when dil. $H_{2}S{O}_4$ is electrolysed when 2F of charge is passed at STP is:

1. 33.6 L
2. 44.8 L
3. 22.4 L
4. 11.2 L

Q.

Is ionic bond formation exothermic or endothermic?

Q.

Can chromium be obtained by electrolysis?

Q. The volume of gases evolved when dil. $H_{2}S{O}_4$ is electrolysed when 2F of charge is passed at STP is:

1. 22.4 L
2. 11.2 L
3. 33.6 L
4. 44.8 L

Q. Electrolysis of $NaCl\left(aq\right)$ is carried out using inert electrodes, choose the correct option:

1. When concentrated $NaCl$ is used, oxygen gas is liberated at anode.
2. When dilute $NaCl$ is used, chlorine gas is liberated at anode.
3. When concentrated $NaCl$ is used, chlorine gas is liberated at anode.
4. When dilute $NaCl$ is used, oxygen gas is liberated at anode.

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. 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. 96500
3. 193000
4. 48250

Q. Match the statements in Column I with suitable statements in Column II.
$\begin{array}{cccc}& \text{Column I}& & \text{Column II}\\ \text{a.}& \text{A gas in contact with an}& \text{p.}& \text{Electrode potential}\\ & \text{inert electrode}& & \\ \text{b.}& \text{The potential difference in}& \text{q.}& O_2\text{at anode metal and}\\ & \text{volts between the two}& & \text{the solution of metal ion}\\ & \text{electrodes}& & \\ \text{c.}& Li\text{metal has the lowest}& \text{r.}& H_2\left(g\right)/Pt\text{potential}\\ & \text{standard electrode}& & \\ & \text{potential}& & \\ \text{d.}& \text{Electrolysis of aq.}N{a}_{2}S{O}_4& \text{s.}& \text{Strongest reducing agent}\\ & \text{using}Pt\text{electrodes}& & \\ & & \text{t.}& -3.06\text{Volt}\end{array}$

1. (a – r; b – p; c – s; d – q)
2. (a – r; b – s; c – t; d – q)
3. (a – p; b – r; c – s; d – q)
4. (a – r; b – p; c – q; d – s)

Q. How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of diborane?
[Atomic weight of $B=10.8u$, $1F=96500C$]

1. 3.2 hours
2. 1.6 hours
3. 6.4 hours
4. 0.8 hour

Q. Group I cations are precipitated as ________.

1. Sulphides
2. Nitrates
3. Carbonate
4. Chlorides

Q.

State the observations at the anode and at the cathode during electrolysis of:

fused lead bromide using graphite electrodes

Q. $C{l}_2$(g) is produced during the electrolysis of an aqueous solution of $NaCl$ at the anode.

1. True
2. False

Q. Among the electrolytes given below $K_{2}S{O}_4,BaC{l}_2,A{l}_2(S{O}_4{)}_3$ and $N{H}_{4}Cl$ which will be the most effective coagulating agent for $S{b}_2{S}_3$ sol?

1. $K_{2}S{O}_4$
2. $BaC{l}_2$
3. $N{H}_{4}Cl$
4. $A{l}_2(S{O}_4{)}_3$

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. Group I cations are precipitated as ________.

1. Chlorides
2. Sulphides
3. Carbonate
4. Nitrates

Q.

Which of the following compounds will not undergo decomposition on passing electricity through aqueous solution

[MP PET 2001]

1. Sugar

2. Sodium Chloride

3. Sodium Bromide

4. Sodium Acetate

Q. In which of the following titrations, conductivity increases upon the addition of the titrant?

1. Addition of $NaOH$ to $HCl$ solution
2. Addition of acetic acid to ammonia solution
3. Addition of acetic acid to $NaOH$ solution
4. Addition of ammonia to $HCl$ solution

Q. Group I cations are precipitated as ________.

1. Nitrates
2. Chlorides
3. Carbonate
4. Sulphides

Q.

During the electrolysis of copper (II) sulphate solution using platinum as cathode and carbon as anode: What do you observe at the cathode and at the anode.

Q.

Complete the following ionic equations in reference to electrolysis and electroplating.

$4{\mathrm{OH}}^{-}\to \mathrm{\_\_\_\_\_}+\mathrm{\_\_\_\_\_}$

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 : $O_2$

4. Anode : $C{l}_2$

Q.

Electrolytes when dissolved in water dissociates into ions because

[CPMT 1974, 78; MNR1983]

1. They are unstable

2. The water dissolves it

3. The force of repulsion increases

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

Q. Which of the following option(s) is/are incorrect regarding electrochemical series ?

1. All of the above.
2. Negative value of $E^{\circ }$ signifies that the redox couple is a stronger oxidising agent than the $H^{+}/H_2$ couple
3. Spontaneity and feasibility of the cell can be easily predicted.
4. Polarity of the electrode system and the electrode reaction can be easily predicted.

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. $Pt|H_2(g,P_1)|HCl\left(0.1M\right)|H_2(g,P_2)|Pt$

A concentration cell is formed by two hydrogen electrodes having hydrogen gas at different pressures $P_1\&P_2$, dipped in the same electrolytic solution $\left(0.1MHCl\right)$ at $298K$.
Choose the correct option :

1. $E_{cell}^0<0$
2. Higher the concentration of electrolyte, more is the EMF generated.
3. For spontaneous reaction to take place,
   $P_1>P_2$
4. $E_{cell}^0>0$

Q.

If the current is passed into the solution of an electrolyte

[AIIMS 1979]

1. Anions move towards anode, cations towards cathode

2. Anions and cations both move towards anode

3. Anions move towards cathode, cations towards anode

4. No movement of ions takes place

Q. How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of diborane?
[Atomic weight of $B=10.8u$, $1F=96500C$]

1. 3.2 hours
2. 1.6 hours
3. 6.4 hours
4. 0.8 hour

Q.

Write the equation taking place at the anode during the purification of the Anode?

Q.

Strong electrolytes are those which

[MNR 1983]

1. Dissolve readily in water

2. Conduct electricity

3. Dissociate into ions at high dilution

4. Completely dissociate into ions at all dilutions