Why do a can of soda dissolve the cover of m and m quicker?

A can of soda can dissolve the candy coating of M&M's more quickly due to its acidic content, primarily from phosphoric acid and carbonation. The acidity can break down the sugar in the candy shell, while the carbonation can enhance the reaction by increasing the movement of molecules. This combination accelerates the dissolution process compared to other liquids. Additionally, the sugar and other ingredients in the soda can contribute to this effect.