What is dry acid deposition composed of?

Dry acid deposition refers to the deposition of acidic substances in the atmosphere that do not occur in liquid form, such as rain or snow. Instead, it comprises acidic dust and gases that settle onto surfaces without precipitation. Common components of dry acid deposition include sulfur dioxide (SO2) and nitrogen oxides (NOx), which can react with water vapor, oxygen, and other substances in the atmosphere to form acids that are then deposited as solid particles or gases.

This process is particularly significant in areas where industrial activities release these pollutants into the air. Unlike wet deposition, which is commonly associated with acidic rain or snow, dry deposition can affect soil, water bodies, and vegetation even in the absence of precipitation, leading to environmental harm. Thus, the correct understanding of dry acid deposition highlights its reliance on particulate matter and gaseous forms of acidity, primarily found in the choice mentioning acidic dust and gases.