Which reaction involves a redox process where the oxidizing agent loses oxygen without electron transfer to a metal?
In SO₃ + S → 2SO₂, SO₃ (S: +6 to +4) loses oxygen and is reduced, oxidizing S (0 to +4), no metal involved.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Redox Titrations and Equivalent Weight and Normality