Question

The value of molar conductance of HCl is greater than that of NaCl at a given temperature and concentration because :

• A. ionic mobility of HCl is greater than that of NaCl
• B. the dipole moment of NaCl is greater than that of HCl
• C. NaCl is more ionic than HCl
• D. HCl is Bronsted acid and NaCl is a salt of a strong acid and strong base

Answer 1

The correct option is A ionic mobility of HCl is greater than that of NaCl

The molar conductance of an ion is directly proportional to its ionic mobility.

Thus when ionic mobility is high, the molar conductance of the ion is high and the molar conductance of the electrolyte containing that ion is high.

The ionic mobility of $H^{+}$ ion is greater than that of $N{a}^{+}$.

Because of the lower mass of H, the velocity of $H^{+}$ ions is more than that of $N{a}^{+}$ ions. Smaller the cation higher is the molar conductivity.

So, molar conductivity of HCl is greater than that of NaCl at a particular temperature.

Hence, option A is correct.