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Question
Suggest a way to determine the `∧_"m"^∘`value of water.
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Solution
Water is a weak electrolyte. Its `∧_"m"^∘`value can be determined with the help of Kohlrausch's law.
`∧_"m"^∘("HCl") = ∧_"m"^∘("H"^+) + ∧_"m"^∘("Cl"^-)` ...(i)
`∧_"m"^∘("NaOH") = ∧_"m"^∘("Na"^+) + ∧_"m"^∘("OH"^-)` ...(ii)
`∧_"m"^∘("NaCl") = ∧_"m"^∘("Na"^+) + ∧_"m"^∘("Cl"^-)` ...(iii)
By adding (i) and (ii) and subtracting (iii) we get
`∧_"m"^∘("H"_2"O") = ∧_"m"^∘("H"^+) + ∧_"m"^∘("OH"^-)`
= `∧_"m"^∘("HCl") + ∧_"m"^∘("NaOH") - ∧_"m"^∘("NaCl")`
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