Acidity of naphthol vs hydroxynaphthoquinone I have the following two compounds whose acidity I need to compare. I tried drawing out the resonating structures but I seem to not be able to draw final conclusion.



I know that the conjugate base of Q has more resonance structures, but R is still more acidic according to the book, with its resonance looking like this:



Why such resonance makes it more acidic?
For naphtol both the acidic and the basic forms have many resonance structures along the two fused benzene cycles. However, in the case of 2-hydroxy-1,4-naphthoquinone, the basic conjugated form creates novel resonance structures that engage the double bond of the quinone cycle as seen in the written resonance structure in the question. The novel resonance structures of the basic forms will stabilize the basic form. 
Therefore, the hydroxyl group in 2-hydroxy-1,4-naphthoquinone has higher tendency to lose the hydrogen ion than the hydroxyl group in naphtol. This explains the higher acidity of 2-hydroxy-1,4-naphthoquinone in comparison with naphtol.