Acid Rain and Its Effects Acid rain is the result of the burning of fossil fuels, which release nitrogen oxides, and sulfur dioxide into the atmosphere. When the two compounds react in the atmosphere, with water, oxygen, and oxidants, they form acid rain, or acid deposition. Electric utility plants mostly emit the sulfur dioxide and nitrogen oxides Acid rain is deposited back to earth in a wet form (rain, snow, and sleet). Acid deposition is deposited as a fog or gas. Because acid deposition is solid particles that can settle out on surfaces, it is often more acidic and damaging than acid rain. Scientists can determine the acidity of rain by measuring the