If a volcanic eruption lowers the ph of the water in a nearby lake, how might this lowered ph harm living things in the lake?

Many plants and animals are evolved to live in a specific pH, especially if its only source is the rain, so there may be a mass extinction because there will be little time to adapt. Over time, the creatures may adapt, but im the short term, there will be a lot death.

The arrangements of lipids in the membrane makes the cell semi permeable .