Match List - I with List - II List - I (Parmeter) List - II (Unit) (a) Cell constant (i) S\,cm^2mol^ - 1 (b) Molar conductivity (ii) Dimensionless (c) Conductivity (iii) m^ - 1 (d) Degree of dissociation of electrolyte (iv) \Omega ^ - 1m^ - 1 Choose the most appropriate answer from the options given below :

(a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)

(a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)

(a)-(i), (b)-(iv), (c)-(iii), (d)-(ii)

(a)-(ii), (b)-(i), (c)-(iii), (d)-(iv)

Electrochemistry PYQ — JEE Main 2021 · 31 Aug · Shift 2 · Q5 with Solution

Match List - I with List - II

	List - I (Parmeter)		List - II (Unit)
(a)	Cell constant	(i)	$S\,c{m^2}mo{l^{ - 1}}$
(b)	Molar conductivity	(ii)	Dimensionless
(c)	Conductivity	(iii)	${m^{ - 1}}$
(d)	Degree of dissociation of electrolyte	(iv)	${\Omega ^{ - 1}}{m^{ - 1}}$

Choose the most appropriate answer from the options given below :

View written solutionFree

Correct answer: A

We match each parameter in List-I with the correct unit in List-II.

Cell constant is defined as:

\text{Cell constant} = \frac{l}{A}

where $l$ is distance between electrodes and $A$ is area of cross-section.

So its unit is:

\frac{\text{length}}{\text{area}} = \frac{m}{m^2} = m^{-1}

Thus,

(a) \to (iii)

Molar conductivity $\Lambda_m$ has units:

S\,cm^2\,mol^{-1}

(or equivalently $S\,m^2\,mol^{-1}$ in SI form)

From the list, this corresponds to:

(b) \to (i)

Conductivity $\kappa$ has SI unit:

\Omega^{-1} m^{-1}

Thus,

(c) \to (iv)

Degree of dissociation $\alpha$ is a ratio:

\alpha = \frac{\text{number dissociated}}{\text{total number initially present}}

So it has no unit, i.e. it is dimensionless.

Thus,

(d) \to (ii)

The correct matching is:

(a)-(iii),\quad (b)-(i),\quad (c)-(iv),\quad (d)-(ii)

This corresponds to Option A.

Stored correct answer: A

Derived answer: A

So, the derived answer agrees with the stored correct answer.