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Solubility. Like dissolves like. Organic compounds are not expected to be soluble in water. Rule of Thumb: C/O ratio. However,. If the organic compound can be ionized. It is more likely to be water-soluble. since ionic compounds are polar, and thus water-soluble.
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Solubility Like dissolves like Organic compounds are not expected to be soluble in water Rule of Thumb: C/O ratio
However, If the organic compound can be ionized It is more likely to be water-soluble since ionic compounds are polar, and thus water-soluble Requirement: the presence of an ionizable atom/group What is an ionizable atom/group one which can form a conjugate acid or conjugate base upon treatment with an acid or base
Classification of Organic Compounds from a solubilitypoint of view
phenolate But
Phenols have very different acid-base properties compared to alcohols a phenolate, the conjugate base of a phenol, is much more stable than an alkoxide phenolate the conjugate base of an alcohol alkoxide
extensive charge delocalization into the aromatic ring no charge delocalization here
extensive charge delocalization into the aromatic ring electron/charge delocalization is a stabilizing factor more stable weaker conjugate base the conjugate base of a stronger acid is a weaker conjugate base thus a phenols is a stronger acid than an alcohol
all insoluble with water if C/O ratio > 4 not strongly basic enough to ionize in the presence of NaOH (aq) (remember why not) But oxygen will protonate upon treatment with H2SO4 (conc)
Samples to be tested N-ethylaniline a-naphthol (a phenol) benzoic acid butanol para-dichlorobenzene