What type of oxides is formed by non-metals?

Oxides with pH <=7 Amphoteric oxides Oxides with pH > 7 Oxides which are acidic

Oxides which are acidic

Non-metals form acidic oxides because upon dissolution in water they liberate free H+ ions. Oxides with pH ≤7 also include neutral oxides and not acidic only. Oxides with pH > 7 are basic in nature. Amphoteric oxides behave both like acid and base.