Assertion `(A:` Cell constant is the `EMF` of a cell.
Reason `(R):` Cell constant is determined by using saturated `KCl` solution.

Options

A. If both `(A)` and `(R)` are correct, and `(R)` is the correct explanation of `(A)`.
B. If both `(A)` and `(R)` are correct, but `(R)` is not the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R)` is incorrect.
D. If `(A)` is incorrect, `(R)` is correct.

Answer

D

Explanation

`(A)` is incorrect. Cell constant `(G^(**))=(1)/(a)cm^(-1)`
`(R)` is correct . `G^(**)` is determined by using `KCl` solution since its conductivity is known accurately at various concentrations and at differne temperature.