Question

The ionic conductance of \[B{a^{2 + }}\]and \[C{l^ - }\] are respectively 127 and \[76{\Omega ^ - }\]\[c{m^2}\] as infinite dilution. The equivalent conductance (in\[{\Omega ^{ - 1}}c{m^2}\]) of \[BaC{l_2}\] at infinite dilution will be what?
a.) 340
b.) 139.5
c.) 253.5
d.) None

Answer 1

Hint: An electrolyte's equivalent conductance is defined as the conductance of a volume of solution that contains one equivalent weight of dissolved material when placed between two parallel electrodes 1 cm apart, and large enough to contain all of the solution between them.

Complete answer:
The equivalent weight of
\[BaC{l_2} = \dfrac{{{\text{Molecular weight}}}}{2}\]
\[\lambda _m^\infty \;{\text{for }}BaC{l_2} = \lambda _m^\infty [B{a^{2 + }}] + 2\lambda _m^\infty (C{l^ - })\]
                           \[ = \dfrac{1}{2}\lambda _m^\infty [B{a^{2 + }}] + \lambda _m^\infty (C{l^ - })\]
                           \[ = \dfrac{1}{2}(127) + 76\]
\[\lambda _m^\infty \;{\text{for }}BaC{l_2} = 139.5{\Omega ^{ - 1}}c{m^2}\]

Hence, option B is the right answer.

Note: Ionic conductance is a measure of a substance 's propensity toward ionic conductivity. It includes the passage of an ion from one location to another through defects in a solid or aqueous solution's crystal lattice. One current mechanism is ionic conduction. Usually ions occupy fixed positions in the crystal lattice in solids, and do not move. But ionic conduction can occur, particularly as the temperature rises. In batteries materials that possess this property are used.
Infinite dilution was a concept found in chemistry which was initially used to study the different solvents, liquids, and solutes, the dissolved substances in solvents. This theory is used to check solutions' properties, and to extrapolate or estimate their chemical reactions in various conditions. Infinite dilution is also characterized as a solution which contains so much solvent that there is no change in concentration by adding more liquid. This means that the properties of the solute — the substratum particles — and the system will not change, no matter how much solvent is added to the solution.