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what is meant by solubility here? CIE exam paper

Deffect

i can't solve this problem

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Original post by Deffect

i can't solve this problem

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It means do the compounds make other species when reacting with acids or bases which are then soluble in water.

For example, amines are usually insoluble basic compounds, which dissolve in acidic solution because the amine group protonates to make the conjugate acid, which is ionic and hence soluble.

R-NH₂ + H⁺ --> R-NH₃⁺

Reply 2

macpatgh-Sheldon

For the individual isomers:

E. Neither the amide group (CO-NH) NOR the alcohol group (-OH) will ionize INSOLUBLE IN BOTH

F. The amino group confers alkalinity (as in amino acids) so will react with HCl and form ions; the carboxylic group (-COOH - acidic) will react with NaOH (alkali) SOLUBLE IN BOTH.

G. Amine will react with acid (HCl) as with F above. SOLUBLE IN ACID

H. Amide will not react as with E. The phenol group acts as a very weak acid, and its H+ is drawn away from the -OH group (which is attached to one of the Cs on the aromatic ring) by NaOH SOLUBLE IN NaOH

M

(edited 7 years ago)

Reply 3

Deffect

thanks