The limiting molar conductivities of $\mathrm{NaCl}$, $\mathrm{NaI}$ and $\mathrm{RbI}$ are $12.7$, $10.8$ and $9.1\,\mathrm{mS\,m^{2}\,mol^{-1}}$, respectively. The limiting molar conductivity of $\mathrm{RbCl}$ would be
(a)$32.6\,\mathrm{mS\,m^{2}\,mol^{-1}}$
(b)$7.2\,\mathrm{mS\,m^{2}\,mol^{-1}}$
(c)$14.4\,\mathrm{mS\,m^{2}\,mol^{-1}}$
(d)$11.0\,\mathrm{mS\,m^{2}\,mol^{-1}}$
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
Λ°(RbCl) = Λ°(NaCl) − Λ°(NaI) + Λ°(RbI) = 12.7 − 10.8 + 9.1 = 11.0 mS m² mol⁻¹ (d).