Molecules of benzoic acid (C_6H_5COOH) dimeri | vedclass

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(A) The dimerization reaction is: $2C_6H_5COOH 	o (C_6H_5COOH)_2$Degree of association $\alpha = 0.80$.Van't Hoff factor $i = 1 - \alpha + \frac{\alp

Vedclass · Accepted Answer

$2.44$

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(A) The dimerization reaction is: $2C_6H_5COOH 	o (C_6H_5COOH)_2$Degree of association $\alpha = 0.80$.Van't Hoff factor $i = 1 - \alpha + \frac{\alpha}{n} = 1 - 0.8 + \frac{0.8}{2} = 0.2 + 0.4 = 0.6$.Depression in freezing point formula: $\Delta T_f = i 	imes K_f 	imes m$,where $m$ is molality.$m = \frac{w 	imes 1000}{M_{solute} 	imes W_{solvent(g)}} = \frac{w 	imes 1000}{122 	imes 30}$.Substituting the values: $2 = 0.6 	imes 5 	imes \frac{w 	imes 1000}{122 	imes 30}$.$2 = 3 	imes \frac{w 	imes 100}{122 	imes 3} = \frac{w 	imes 100}{122}$.$w = \frac{2 	imes 122}{100} = 2.44 \ g$.

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