Chemical Awareness June 2014 | Page 32

This photo is an example of gypsum formation on stone that has not been directly reached by acid rain (Pubs).

easily” (Nachi). Although the stone or structure will be eroded all around, the material will most likely not be eroded the same on all sides, because different areas of the material may be more in contact with acid rain. Acid rain can also negatively affect pipes, cables, automobiles, along with statues and buildings (NSCU), therefore stone and metals are not the only materials that could be ruined if acid rain is present.

How Else Can Buildings and Statues Be Harmed?

But what if certain areas of the statue or building cannot be directly touched by acid rain? If there is acid rain present around the stone or metal, but not directly in contact with one it, alteration occurs. Alteration is another outcome of acid rain where the stone will change color, and gypsum is formed (Pubs). Gypsum, a mineral that forms as a result of the sulfuric acid, water, and calcite reaction, creates a black rusty layer on carbonate stone exteriors when the carbonate stone is in the presence of SO2, also known as sulfur dioxide gas. However, it is soluble to water, therefore when not directly exposed to the acid rain it remains on the surface of the building or statue and is left on the surface, until soon it peels off and leaves only deteriorated mater (Pubs). While gypsum is seen as black, it is actually white, “...but the crystals form networks that trap particles of dirt and pollutants, so the crust looks black” (Pubs).

What Can We Do to Help?

The main cause of acid rain is pollution and the burning of fossil fuels, therefore reducing the amount of chemicals that occupy the atmosphere will aid to reduce air pollution along with acid rain. There are many programs and groups acting to limit the emissions released by power plants and reduce the chemicals that enter the air (HowStuffWorks). Also, “cars are now fitted with catalytic converters which remove three dangerous chemicals from exhaust gases” (NCSU), resulting in less NOx exhaust and reducing air pollution. Finding alternate sources of energy is also plays a key role in reducing air pollution. Switching to renewable, environmentally-friendly energy sources, such as nuclear and hydroelectric power, would reduce a significant amount of pollution that enters the atmosphere, unlike the burning of nonrenewable sources, such as coal and other fossil fuels, which give off harmful chemicals and is a large component of pollution and acid rain. Factories have also taken a turn to use low sulfur coal, which emits less harmful chemicals into the air, along with low NOx burners, resulting in less NOx output (HowStuffWorks), which will surely cause less acidic rain, and less harm to the environment we currently live in.

directly exposed to the acid rain it remains on the surface of the building or statue and is left on the surface, until soon it peels off and leaves only deteriorated mater (Pubs). While gypsum is seen as black, it is actually white, “...but the crystals form networks that trap particles of dirt and pollutants, so the crust looks black” (Pubs).

What Can We Do to Help?

The main cause of acid rain is pollution and the burning of fossil fuels, therefore reducing the amount of chemicals that occupy the atmosphere will aid to reduce air pollution along with acid rain. There are many programs and groups acting to limit the emissions released by power plants and reduce the chemicals that enter the air (HowStuffWorks). Also, “cars are now fitted with catalytic converters which remove three dangerous chemicals from exhaust gases” (NCSU), resulting in less NOx exhaust and reducing air pollution. Finding alternate sources of energy is also plays a key role in reducing air pollution. Switching to renewable, environmentally-friendly energy sources, such as nuclear and hydroelectric power, would reduce a significant amount of pollution that enters the atmosphere, unlike the burning of nonrenewable sources, such as coal and other fossil fuels, which give off harmful chemicals and is a large component of pollution and acid rain. Factories have also taken a turn to use low sulfur coal, which emits less harmful chemicals into the air, along with low NOx burners, resulting in less NOx output (HowStuffWorks), which will surely cause less acidic rain, and less harm to the environment we currently live in.

This photo portrays how acid rain is accumulated and distributed onto the Earth through precipitation and dust (Nachi).

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