H2SO4 is 75% of acid rain, HNO3 is the other 25%. 75% makes H2SO4 the main component of acid rain.
Try again. Your numbers are WAY off. And I mean way off.
Acid Rain
About one-fourth of the acidity of rain is accounted for by nitric acid (HNO3). In addition to the natural processes that form small amounts of nitric acid in rainwater, high-temperature air combustion, such as occurs in car engines and power plants, produces large amounts of NO gas. This gas then forms nitric acid via Equations 4 and 5. Thus, a process that occurs naturally at levels tolerable by the environment can harm the environment when human activity causes the process (
e.g., formation of nitric acid) to occur to a much greater extent.
What about
the other 75% of the acidity of rain? Most is accounted for by the presence of sulfuric acid (H2SO4) in rainwater. Although sulfuric acid may be produced naturally in small quantities from biological decay and volcanic activity (Figure 1), it is produced almost entirely by human activity, especially the combustion of sulfur-containing fossil fuels in power plants. When these fossil fuels are burned, the sulfur contained in them reacts with oxygen from the air to form sulfur dioxide (SO2). Combustion of fossil fuels accounts for approximately 80% of the total atmospheric SO2 in the United States. The effects of burning fossil fuels can be dramatic: in contrast to the unpolluted atmospheric SO2 concentration of 0 to 0.01 ppm, polluted urban air can contain 0.1 to 2 ppm SO2, or up to 200 times more SO2! Sulfur dioxide, like the oxides of carbon and nitrogen, reacts with water to form sulfuric acid (Equation 6).