Acid Rain and Smog

CaCOj (marble) +2H2SO4 Ca(HS04)2 (water soluble) -i-HjO-hCOj 

2CaC03 + 2H (from the acid) Ca (HCO3) 2 (water soluble) + Ca  

That is, the marble will be washed away by acidic rain. 

The internal combustion engine in our car bums gasoline fuel. Gasoline is a mixture of hydrocarbons that are made of elements carbon and hydrogen. So when 

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Figure 10.1 Products of combustion contribute in vanous ways to the greenhouse effect, acid rain, and smog. (From Smith and Petela, Chem. Eng., 523 32, 1992 reproduced by permission of the Institution of Chemical Engineers.)...

Once MNT-enabled solar energy becomes the exclusive energy source, problems such as acid rain and smog should not exist. In addition, future vehicles that are constructed from nano-materials, driven by nano-electromechanical systems and powered by hydrogen fuel cells (see Fig. 7) or solar cells (see Fig. 8) should totally eliminate transportation-related S02 and NOx emission. Therefore, the anthropogenic release of S02 and NOx that has assaulted the atmosphere since the Industrial Revolution should be ceased further acidification of the environment and the threat to human health will be relieved [31-33]. 

Cons (1) The emission pollution to the environment (CO2, NOx, SO2, Hg, etc.) leads to global warming, acid rain, and smog. 

Nitrogen oxides (NO ) are environmental pollutants that lead to hazards such as acid rain and smog. As much as 15% of the total NO emissions comes from the process of coal utilization [70]. It has been an important problem in coal chemistry to understand the pyrolysis mechanism of nitrogen-containing structures. In addition, the role of nitrogen migration in coal is very complex and has not been understood at the molecular level [71,72]. The formation of NO is considered to occur in two steps the... 

The waste streams created by utility systems tend, on the whole, to be less environmentally harmful than process waste. Unfortunately, complacency would be misplaced. Even though utility waste tends to be less harmful than process waste, the quantities of utility waste tend to be larger than process waste. This sheer volume can then result in greater environmental impact than process waste. Gaseous combustion products contribute in various ways to the greenhouse effect, acid rain and can produce a direct health hazard because of the formation of smog. The aqueous waste generated by utility systems can also be a major problem if it is contaminated. 

Atmospheric aerosols usually means the solid and liquid particles in the earth s atmosphere, excluding the solid and liquid water particles in clouds, fog, and rain. Although very tenuous and highly variable, they act as condensation nuclei for cloud droplets, alter the optical properties of clouds, and possibly play a role in the formation of smog and acid rain. And an understanding of their optical properties is needed for many applications ... 

Atmospheric nitrogen is also converted into NO in hot airplane and automobile engines, a process that contributes to the problem of acid rain and the formation of smog. Small amounts of nitric oxide occur naturally in our bodies, where it acts as a neurotransmitter, helps to dilate blood vessels, and participates in other physiological changes (Section 2.10). 

Nitrogen oxides (NOx) such as nitric oxide (NO), nitrous oxide (N2O), and nitrogen dioxide (NO2) make one of fhe most common groups of air pollufanfs. They are released mainly from internal combustion engines and furnaces and are considered fo be harmful atmospheric pollutants, as they can cause acid rain, photochemical smog, and greenhouse effects (Zhou et ah, 2007). 

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