The specific conductivity of a normal solution of $KCl$ at $25 \, ^oC$ is $0.002765 \, S \, cm^{-1}$. If the resistance of the cell is $400 \, \Omega$,what is the cell constant (in $cm^{-1}$)?

At $298 \text{ K}$,the molar conductivity of $x\% \text{ (w/w)}$ $MX$ solution (aqueous) is $123.5 \text{ S cm}^2 \text{ mol}^{-1}$. The conductance of the same solution is $1.9 \times 10^{-3} \text{ S}$. The value of $x$ is . . . . . . $\times 10^{-2}$. (Given: cell constant = $1.3 \text{ cm}^{-1}$; molar mass of $MX$ is $75 \text{ g mol}^{-1}$,density of aqueous solution of $MX$ at $298 \text{ K}$ is $1.0 \text{ g mL}^{-1}$)

Which of the following units of electrical measurement is not equivalent to $1$ Siemen?

The metal which is the best conductor of electricity is

Given below are two statements $:$
Statement $I :$ Mohr's salt is composed of only three types of ions$-$ferrous,ammonium and sulphate.
Statement $II :$ If the molar conductance at infinite dilution of ferrous,ammonium and sulphate ions are $x_1, x_2$ and $x_3 \ S \ cm^2 \ mol^{-1}$,respectively then the molar conductance for Mohr's salt solution at infinite dilution would be given by $x_1+x_2+2 x_3$
In the light of the given statements,choose the correct answer from the options given below $:$

Which solution of $NaCl$ will show the highest resistance during the passage of current (in $N$)?