Industrial cleaning (removal of rust scale and deposits). Chemical processing where stronger acidity is required. Battery and electrochemical applications (acidic electrolytes). Environmental studies (monitoring polluted water systems).

Enhances dissolution of metals and mineral deposits. Supports specific chemical reactions. Helps detect and study pollution effects. Used where acidic conditions are necessary for processing.

Clearly acidic. Often associated with polluted rainwater or acid rain. More corrosive and reactive than mildly acidic water.