State and derive Ostwaid dilution law fo...

State and derive Ostwaid dilution law for a weak electrolyte.

Text Solution

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At constant temperature the degree of dissociation of weak electrolyte process with dilution in such a way that the value of the `(alpah^2 c)/(1- alpha)` remains constant.
Let us consider weak acid
`HA leftrightarrow H^(+)+ A^-`
c 0 0
`c-a c ca ca `
Initial concentration
Equilibrium concentration
Applying law of mass action
`K_a=([H^+][A^-])/([HA])`
`K_a=(ca times ca)/(c (1-a))=(c a^2)/(1-a)`

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Ostwald's dilution law is applicable to

Strong electrolytes only

weak electrolytes only

non electrolytes

strong and weak electrolytes

The ostwald dilution law is obeyed by

Sodium oxalate

Ammonium oxalate

Sodium acetate

Ammonium hydroxide

Ostwald's dilution law is not obeyed by

`CH_3COOH`

`NH_4Oh`

HCN

KCl