Any type of precipitation that contains acidic elements, such as sulfuric or nitric acid, that falls to the ground from the atmosphere in wet or dry forms is referred to as acid rain, also known as acid deposition. Rain, snow, fog, hail, and even acidic dust might fall under this category.

SO2 and NOX are the primary causes of acid rain and NOX is the main contributing factor. The main reason why acid rain rises is to stabilize, or remove, the calcium carbonate that forms in water when sulfur dioxide reacts with oxygen.SO2 and NOX form sulfuric and nitric acids, which can be lethal to plants. When combined with water, these acids react with calcium carbonate, forming calcium sulfate, which can be deadly to plants.Because acid rain is caused by SO2 and NOX, the most effective way to reduce the damage caused by acid rain is to reduce these emissions. These emissions are not just limited to factories or power plants.SO2 and NOX are emitted by facilities such as power plants, chemical plants, and paper mills. These emissions combine with other chemicals and water to create acid rain. The effects of acid rain on the environment are potentially serious.For acid rain, the greenhouse gases that are released form sulfuric and nitric acids. These acids then react with water, oxygen and other chemicals to form sulfuric and nitric acids.The sulfuric acid that is released by the power plants is the most damaging. The nitric acid is much less harmful, but it can still have an impact on human health.

The quantity of acidity in the atmosphere that falls as dry deposition to the soil depends on how much rain falls in a given area. For instance, compared to a location that receives several inches of rain each year, desert environments have a larger ratio of dry to wet deposition.

Form of Acid 

Wet Deposition

What we most frequently associate with acid rain is wet deposition. In addition to rain, snow, fog, or hail, sulfuric and nitric acids that have generated in the atmosphere also fall to the eart

Dry Deposition

In the absence of moisture, acidic particles and gases can potentially deposit from the environment called dry deposition. The gases and acidic particles may swiftly settle to surfaces (water bodies, vegetation, or buildings) or they may react while being transported through the atmosphere to produce larger particles that may be dangerous to human health. The next rain will wash away the collected acids, causing acidic water to flow over and through the earth and injure plants and creatures like fish and insects.