Can caves be formed by acid rain?

Yes, caves can be formed by acid rain, although it is not the primary mechanism for cave formation. Acid rain, which contains sulfuric and nitric acids, can enhance the dissolution of limestone and other soluble rocks, leading to the development of underground voids over time. This process contributes to karst topography, where features like sinkholes and caves are created as the rock is gradually eroded away. However, most caves primarily form through the natural processes of groundwater chemistry and erosion rather than directly from acid rain.