Question

The molar ionic conductivities of \[\ce{Ca^2+}\] and \[\ce{CI-}\] are 119.0 and 76.3 S cm² mol⁻¹ respectively. The value of limiting molar conductivity of \[\ce{CaCl2}\] will be ______.

Options

• 195.3 S cm² mol⁻¹

• 43.3 S cm² mol⁻¹

• 314.3 S cm² mol⁻¹

• 271.6 S cm² mol⁻¹

Answer 1

The molar ionic conductivities of \[\ce{Ca^2+}\] and \[\ce{CI-}\] are 119.0 and 76.3 S cm² mol⁻¹ respectively. The value of limiting molar conductivity of \[\ce{CaCl2}\] will be 271.6 S cm² mol⁻¹.

Explanation:

\[\ce{CaCl2 -> Ca^2+ + 2Cl-}\]

Limiting molar conductivity of \[\ce{CaCl2}\] can be calculated as:

\[\ce{∧°m(CaCl2) = ∧°Ca^2+ + 2 × ∧°Cl-}\]

= 119.0 + 2 × 76.3

= 271.6 S cm² mol⁻¹