Consider the following:

1. Oxides of Hydrogen

2. Oxides of Nitrogen

3. Oxides of Sulphur

Which of the above is/are cause/causes of acid rain?

The correct answer is  2 and 3. 

Key Points

• Acid rain refers to any precipitation (rain, fog, mist, and snow) that is more acidic than normal (pH of less than 5.6).
• pH below 7 is considered to be acidic. the pH of water is 7 and above 7 all are Bases.
• It can have harmful effects on plants, aquatic animals, and infrastructure through the process of wet deposition.
• Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides which react with the water molecules in the atmosphere to produce corresponding sulphuric and nitric acids which fall along with rain droplets on the ground.

Additional Information

• Acid rain can be extremely harmful to forests.
• Acid rain that seeps into the ground can dissolve nutrients, such as magnesium and calcium, that trees need to be healthy.
• Acid rain also causes aluminum to be released into the soil, which makes it difficult for trees to take up water.
• Trees that are located in mountainous regions at higher elevations, such as spruce or fir trees, are at greater risk because they are exposed to acidic clouds and fog, which contain greater amounts of acid than rain or snow.