Out of o-nitrophenol and o-cresol which is more acidic? 

This is a short answer type question as classified in NCERT Exemplar

Out of o-nitrophenol and o-cresol, o-nitrophenol  is more acidic due to the -I effect and -R effect of -NO₂ group as the -NO₂ group is an electron withdrawing group whereas the -CH₃ group is electron releasing group and has +I effec