The molar conductivity of NH4Cl, OH and Cl at infinite dilution is 150, 200 and 75 , respectively. I — Electrochemistry Chemistry Question

💡 Solution & Explanation

$\Lambda_m^\circ(NH_4^+) = \Lambda_m^\circ(NH_4Cl) - \Lambda_m^\circ(Cl^-) = 150 - 75 = 75\ \Omega^{–1}\text{cm}^2\text{mol}^{–1}$. $\Lambda_m^\circ(NH_4OH) = \Lambda_m^\circ(NH_4^+) + \Lambda_m^\circ(OH^-) = 75 + 200 = 275\ \Omega^{–1}\text{cm}^2\text{mol}^{–1}$. Degree of dissociation $\alpha = \Lambda_m / \Lambda_m^\circ = 22 / 275 = 0.080$. Therefore, correct answer is C.