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Electrochemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryElectrochemistry2 Marks
Question
What is conductance and conductivity (specific conductance)?
✓

Answer

→ "The inverse of resistance, R is called conductance, G"$
\begin{array}{l}
G =\frac{1}{ R }=\frac{ A }{\rho \cdot l} \\
G = K \left(\frac{ A }{l}\right)\left(\because K \text { conductivity }=\frac{1}{\text { resistivity } \rho}\right)
\end{array}
$
→ The SI unit of conductance is siemens, represented by the symbol ' S ' and is equal to ohm $^{-1}$ (also known as mho) or $\Omega^{-1}$
→ "The inverse of resistivity, called conductivity (specific conductors) is represented by the symbol, k (greek, kappa)"
→ The SI unit of conductivity are $S\ m ^{-1}$ but quite often, k is expressed in $S$ $cm ^{-1}$
→ Conductivity of a material in $S\ cm ^{-1}$is its conductance when it is 1 m long and its area of crosss sections $1$ $ m^2$.
$1$ $S$ $cm ^{-1}=100 S$ $m ^{-1} \text .$

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