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Tasya [4]
3 years ago
6

The titration of 25.00 ml a 0.125 m hclo4 solution requires 27.07 ml of koh to reach the endpoint. what is the concentration of

the koh
Chemistry
1 answer:
agasfer [191]3 years ago
5 0

Answer : The concentration of the KOH is, 0.115 M

Explanation :

Using dilution law,

n_1M_1V_1=n_2M_2V_2

where,

n_1 = basicity of an acid = 1

n_2 = acidity of a base = 1

M_1 = concentration of HClO_4 = 0.125 M

M_2 = concentration of KOH = ?

V_1 = volume of HClO_4 = 25 ml

V_2 = volume of NaOH = 27.07 ml

Now put all the given values in the above law, we get the concentration of the KOH.

1\times 0.125M\times 25ml=1\times M_2\times 27.07ml

M_2=0.115M

Therefore, the concentration of the KOH is, 0.115 M

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c )ΔG =  1.8 x 10⁴ J

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Using Hess law to calculate  ΔHºrxn we have

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- ΔG / RT = lnK  ∴ K = exp (- ΔG / RT)

K = exp ( - 1.8 x 10⁴ J /( 8.314 J/K  x 873 K)) = 8.2 x 10⁻²

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