Answer
The proton on the right is more acidic.
Work Step by Step
If we remove the left proton, the conjugate base will have these changes:
- The Hydrogen on the left will be removed.
- The Oxygen that was connected to the Hydrogen will get a negative charge, because the electrons that were making the bond will turn into a lone pair.
If we remove the proton on the right, the conjugate base will have these changes:
- The Hydrogen on the right will be removed.
- The Sulfur that was connected to the hydrogen will get a negative charge, because the electrons that were making the bond will turn into a lone pair.
Since Sulfur has a better ability to stabilize charges, compared with Carbon, the proton on the right will be more acidic.
** If the atoms are in the same column, the bigger one will be more stable.
