Conductance and Conductivity

Q. How would you determine the standard electrode potential of the system ${\text{Mg}}^{2+}|\text{Mg}$ ?

Q. Aqueous solution of which of the following compounds is the best conductor of electric current?

1. Ammonia, $N{H}_3$
2. Fructose, $C_6{H}_{12}{O}_6$
3. Acetic acid, $C_2{H}_4{O}_2$
4. Hydrochloric acid, $HCl$

Q.

Among iron and mercury which is a better conductor of electricity and why?

Q.

The resistance of a conductor is directly proportional to?

Q.

Why is an aqueous solution of $\mathrm{HCl}$ is a good conductor of electricity?

Q.

Kohlrausch's Law is applicable:

1. to aqueous solution of strong electrolytes

2. applicable to electrolytes dissolved in a solvent of low polarity only.

3. to electrolytic solutions at infinite dilution

4. to electrolytes at temperature above room temperature

Q. Conductivity of a cell $\left(\kappa \right)$ is equal to

where,
$R$ is resistance
$G$ is conductance
$G^{\ast }$ is cell constant
$l$ is length of the conducting cell
$A$ is cross section of cell

1. $\frac{1}{R}\times \frac{l}{A}$
2. $\frac{G}{G^{\ast }}$
3. $\frac{G^{\ast }}{R}$
4. $\frac{1}{G}\times \frac{A}{l}$

Q. How is the electrical conductance of a conductor relates with length and area of cross section of the conductor?
where,
$G$ is conductance
$l$ is length of the conductor
$A$ is area of cross section of the conductor
$\kappa$ is conductivity

1. $G=l\times A\times {\kappa }^{-1}$
2. $G=\kappa \times l\times A^{-1}$
3. $G=\kappa \times A\times l^{-1}$
4. $G=\kappa \times l^{-1}\times A^{-1}$

Q. 1M solution of monobasic acid HX has molar conductivity x S cm^2 mol^-1. While molar conductivity of H+ and X- at infinite dilution is 300 s cm^2mol^-1 and 100 S cm^2 mol^-1. The 1M HX solution contains 0.15 M H+. If this 1M is filled in a conducting cell if cell constant 0.1 cm^-1, the conductance is found to be Y ohm^-1. Find the value of 10Y​

Q. The molar conductance of $N{H}_{4}OH$ at 0.01M concentration is 11.3 $oh{m}^{-1}c{m}^{2}mo{l}^{-1}$. The degree of dissociation
of $N{H}_{4}OH$ is
(molar conductance at infinite dilution is 271.1)

1. $4.2\%$
2. $1.3\%$
3. $12.6\%$
4. $41\%$

Q. if k3(fe(cn)6) gets ionized completely in s solution no. of particles in the solution from 1 molecule solute is

Q.

Which of the following shows electrical conduction

[CBSE PMT 1999; AIIMS 1999]

1. Potassium

2. Sodium

3. Graphite

4. Diamond

Q. A current of 2A was passed for 1.5 hours through a solution of CuSO_4 when 1.6 g of copper was deposited. Calculate percentage current efficiency

Q. Unit of ionic mobility is

1. $mse{c}^{-1}volt$
2. $mse{c}^{-1}vol{t}^1$
3. $mse{c}^{-1}$
4. $m^{2}se{c}^{-1}vol{t}^{-1}$

Q.

The dimensional formula of $\frac{L}{R}$ is the same as that of (where $L$ is inductance and $R$ is resistance)

1. ${\left(frequency\right)}^2$

2. time period

3. frequency

4. ${\left(timeperiod\right)}^2$

Q.

To increase the hardness of X-rays in coolidge tube we should :-

1. increase filament current

2. increase filament voltage

3. increase the voltage applied between cathode and anticathode

4. none of these

Q.

Given the standard electrode potentials,

K⁺/K = –2.93V, Ag⁺/Ag = 0.80V,

Hg²⁺/Hg = 0.79V

Mg²⁺/Mg = –2.37V. Cr³⁺/Cr = –0.74V

Arrange these metals in their increasing order of reducing power.

Q. When a solution of specific conductance $1.342{\text{Sm}}^{-1}$ was placed in a conductivity cell with parallel electrodes, the resistance was found to be $170.5\text{ohm}$. The area of the electrodes is $1.86\times {10}^{-4}{\text{m}}^2$ . Calculate the distance between the electrodes.

1. $0.0452\text{m}$
2. $4.25\text{m}$
3. $42.5\text{m}$
4. $0.425\text{m}$

Q. 41. The resistance of 0.5 M solution of an electrolyte in a cell was found to be 50 ohm. If the electrodes in the cell are 2.2 cm apart and have an area of 4.4 CM square then the molar conductivity(S m2 per mol) of the solution is

Q.

The resistance of a N/10 KCl aqueous solution is 245 ohm. If the electrodes in the cell are 4 cm apart and area having 7 cm² each, the molar conductance of the solution will be

A 233

B 2.33

C 23.32

D 0.233

Q. A solution containing 10gm per liter of urea is isotonic with a 5%solution of a nonvolatile solute is a) 200 g/mol b) 300 g/mol c) 250 g/mol d) 350 g/mol

Q. 4. When a certain solution of specific conductivity of 1.4 was placed in a conductivity cell with parallel electrode the resistance was found to be 100 ohm if the distance between electrode become twice and area of the electrode reduce to 1/4 time the resistance of the same solution will be

Q. State True or False?
Conductance is also dependent on the factors on which resistance is dependent

1. True
2. False

Q. SI unit of conductivity is ______.

1. $S{m}^{-1}$
2. $S{s}^{-1}$
3. $S{m}^1$
4. None of these

Q. The minimum equivalent conductance in fused state is of:

1. $CrC{l}_2$
2. $SrC{l}_2$
3. $BeC{l}_2$
4. $MgC{l}_2$

Q. PH3 has lower boiling point than NH3 why?

Q. Equivalent conductance of saturated solution of $BaS{O}_4$ is 200 $oh{m}^{-1}c{m}^{2}eq{v}^{-1}$ and specific conductance is $4\times {10}^{-5}oh{m}^{-1}c{m}^{-1}.K_{sp}$ of $BaS{O}_{4}x\times {10}^{-y}{M}^2$ in scientific notation. The value of (x + y) will be:

Q.

221(b) An apparatus is set up, as shown in the figure the bulb would glow when dilute hydrochloric acid is used as the electrolyte.

Q. The resistance of 0.01 N solution of an electrolyte was found to be 210 ohms at 298 K using a conductivity cell of cell constant of $0.66{cm}^{-1}$. The value of equivalent conductance of solution is:

Q. The specmc conductances in $oh{m}^{-1}c{m}^{-1}$ of four electrolytes $P,Q,R$ and $S$ are given in brackets:
$P(5.0\times {10}^{-5})$
$Q(7.0\times {10}^{-8})$
$R(1.0\times {10}^{-10})$
$S(9.2\times {10}^3)$
The one that offers highest resistance to the passage of electric current is:

1. $R$
2. $P$
3. $Q$
4. $S$