Question

A $KCl$ solution of conductivity $0.14S{m}^{-1}$ shows a resistance of $4.19\Omega$ in a conductivity cell. If the same cell is filled with an $HCl$ solution, the resistance drops of $1.03\Omega$. The conductivity of the $HCI$ solution is ____ $\times {10}^{-2}S{m}^{-1}$. (Round off to the Nearest Integer).

• A. 57.0
• B. 57
• C. 57.00

Answer 1

Answer: (A), (B), (C)

For $KCl$

$k_1=0.14S{m}^{-1}$

$R_1=4.19\Omega$

For $HCl$

$k_2=xS{m}^{-1}$ (Let)

$R_2=1.03\Omega$

$R=\rho \left(\frac{l}{a}\right)\Rightarrow kR=\underset{\text{Cell constant}}{\underset{}{\left(\frac{l}{a}\right)}}$

$k_1{R}_1=k_2{R}_2$

$0.14\times 4.19=1.03\times k_2$

$k_2=0.5695S{m}^{-1}$

$k_2=57\times {10}^{-2}S{m}^{-1}$