Question

The limiting molar conductivities for Nacl, KBr and KCI are 126, 152 and 150 S cm² mol^–1 respectively. The limiting molar conductivity for Na Br is:-

Options

• 278 S cm²mol^–1 

• 176 S cm²mol^–1 

• 128 S cm²mol^–1 

• 302 S cm²mol^–1 

Answer 1

128 S cm²mol^–1  

Explanation:

The limiting molar conductivities of NaCl, KBr and KCl are 126, 152 and 150 S cm²mol^–1 respectively.

The limiting molar conductivity Λ° for NaBr is calculated by the following expression.

`lambda_(NaBr)^oo = lambda_(NaCl)^oo + lambda_(KBr)^oo - lambda_(KCl)^oo`

`lambda_(NaBr)^oo` = 126 + 152 – 150 = 128 S cm²mol^–1