A substance is said to be soluble in water if it is capable of forming H-bonding with water molecule In ohydroxy benzaldehyde due to intramolecular chelation the `OH` group is not avilable to form hydrogen bond with water hence it is sparingly soluble in water On the other hand the `-OH` group is available in p-hydroxy benzaldehyde to form H-bond with water and hence it is more soluble as compared to the o-isomer
(b) These are intramolecular H-bonding in o-hydroxy benzaldehyde while intermolecular H-bonding in p-hydroxybenzaldehyde
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