Morphine is Amphoteic ie.,it has (approximately) equal share of acidity and basicity.
The Phenolic moiety of ring A showers acidic natire and the tertiary Nitrogen containing a lone pair of electrons showers the basicity to the compound.
The Pka is about 8 .Some authors sat its a weak base but most prominantly it can be looked upon as an Amphoteric substance.
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acidic acidic acidic
acidic.
basic or acidic
its acidic
acidic
acidic
Acidic
acidic
acidic
Acidic
acidic
Acidic.