How do acidity changes cause damage in the body, on a molecular level? If I separate NaCl ions through electrophoresis and injected chloride in a patient, would the pH decrease by the presence of the new ions alone? Do the protons and hydroxiles themselves interact with molecules and cause damage? How does getting rid of CO2 or bicarbonate prevent damage?

I am very aware of kidney and lung physiology, i'm aware that the goal is to keep the pH steady, I know proteins denature and shit, but how does this happen and what exactly causes it?