The variation of molar conductivity ( _m ) with the square root of concentration ( C ) is studied for two electrolytes, X and Y. For electrolyte X, the plot of _m versus C is linear and can be extrapolated to zero concentration to obtain a finite limiting value. For electrolyte Y, the plot rises steeply near zero concentration and cannot be extrapolated to find a limiting value. Which of the following pairs correctly

Step-by-step solution

According to the Debye-Hückel-Onsager equation, strong electrolytes show a linear variation of molar conductivity with C and can be extrapolated to zero concentration to find the limiting molar conductivity ( _m^ ). Thus, X must be a strong electrolyte. Weak electrolytes have a low degree of dissociation at higher concentrations, but their dissociation increases steeply as concentration approaches zero. Their _m vs C plot is a steep curve that cannot be extrapolated to the y-axis. Thus, Y must be a weak electrolyte