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Electrochemistry

Question
CBSEENCH12005994

The measured resistance of a conductance cell containing 7.5 x 10–3 M solution of KCl at 25° was 1005 ohms. Calculate (a) specific conductance (b) Molar conductance of the solution. Cell constant = 1.25 cm–1.

Solution
M = 7.5 × 10-3R = 1005 ohms.
(a) Specific conductance (K)
             = 1R×1a where 1a is cell constant.
K=11005 Ohm×1.25 cm-1K = 1.2437×10-3ohm-1cm-1    = 1.2437×10-3S cm-1

(b) 
        Λm= 1000×KM=1000×1.24377.5×10-3m     = 1.2437×10007.5=1.24377.5      = 165.826 Ω-1 cm2 mol-1Λm = 165.826 S cm2 mol-1.