Arrange the following compounds in increasing order of acidity and give a suitable explanation.
The acidity factor of these compounds depends on the type of groups attached. If the group is electron-withdrawing, they increase the acidity of the compound due to (-I) and (-R) effect, which is exactly the case in o-nitrophenol, making it most acidic. Also, due to the (+I) effect depicted by o-cresol, it is weaker than phenol.
So, the correct Increasing order of the acidity of the given compounds: