The culprit of acid rain is ().

Yes, acid rain is not necessarily sulfur oxide. Any anhydride may be the chief culprit of acid rain. Nitrogen oxides emitted by automobile exhaust will cause acid rain.

Seeing that the landlord is so eager to learn, I will help you broaden your knowledge. The following are the main pollutants in automobile exhaust:

1. carbon monoxide (CO)

2. Hydrocarbons

3. Nitrogen oxides (nitrogen oxides)

4. photochemical smog

5. Particulate pollutants (PM)

The specific hazards are:

In recent years, the number of motor vehicles in cities has soared, and a large number of exhaust emissions are the main reasons for the continuous high levels of carbon monoxide and nitrogen dioxide. The photolysis of nitrogen dioxide under strong light causes the increase of ozone concentration, which is the basic reason for the formation of photochemical smog. The composition of particulate matter is complex, and fine particulate matter is the product of human activities, such as carbon particles formed by incomplete combustion of fuel; Volatile hydrocarbons emitted from automobile starting and idling are also the main pollutants of automobile exhaust.

1. 1 carbon monoxide

Carbon monoxide, commonly known as "gas", is a colorless, odorless and toxic gas with stable chemical properties and is the largest atmospheric pollutant in the atmosphere. Carbon monoxide is produced by incomplete combustion of carbonaceous materials. Carbon monoxide in urban atmospheric environment mainly comes from motor vehicle exhaust and coal burning. CO can quickly combine with hemoglobin (Hb) to form carboxyhemoglobin (CO-Hb), which greatly reduces the oxygen transmission capacity of blood and causes dizziness, nausea, headache and other symptoms. In severe cases, it will make cardiovascular work difficult until death.

1.2 Hydrocarbon (HC)

Hydrocarbons (also known as hydrocarbons) include unburned and unburned fuels, lubricating oils and their pyrolysis products, some oxides, such as benzene, aldehydes, olefins and polycyclic aromatic hydrocarbons, and more than 200 complex components. It should be noted that polycyclic aromatic hydrocarbons are strong carcinogens, hydrocarbon components or important substances that cause photochemical smog.

1.3 nitrogen oxides (nitrogen oxides)

Nitrogen oxides are various nitrogen oxides formed during combustion, such as NO, NO2, N2O3, N2O5, etc. , collectively referred to as nitrogen oxides. The concentration of nitrogen oxides in automobile exhaust gas burning gasoline and diesel is quite high, and the nitrogen oxides will eventually be converted into nitric acid and nitrate, which will be removed from the air with precipitation and dust fall. Nitric acid is one of the causes of acid rain. In internal combustion engines, NO is the main component, accounting for about 95%, followed by NO2, accounting for 5%. NO is a colorless and odorless gas with mild irritation and little toxicity. High concentration will cause mild disorder of central nervous system, and NO can be oxidized to NO2. NO2 is a reddish-brown toxic gas with strong irritation, which will affect the heart, liver and kidney.

1.4 photochemical smog

The light blue smoke formed by the mixture of ozone, peracetyl nitrate (PAN) and aldehydes in the ambient air is highly oxidizing and irritating. It is not a pollutant directly discharged from pollution sources, but a secondary pollutant generated by chemical reaction of a large number of primary pollutants such as nitrogen oxides and hydrocarbons discharged from petroleum fuel combustion under ultraviolet radiation. It is the main pollutant of photochemical smog pollution, with strong oxidation and irritation. Reducing visibility is harmful to people's eyes, throat and throat. The following equation is one of the forms of ozone (O3), where hv stands for ultraviolet light and m stands for free radical [2]. In order to prevent photochemical smog, in addition to controlling the main pollutants in industrial processes, it is also important to control automobile exhaust emissions and install exhaust purification devices.

NO2 + hv → NO + O ( 1)，

O + O2 + M → O3 + M (2)

1.5 particulate pollutants (PM)

The harm of particulate matter (also known as particles) to human health is related to its size and composition. The smaller the particles, the longer they stay in the air, and the greater the proportion of particles that stay in the lungs and bronchi after entering the human lungs, the greater the harm. Particulate matter is not only harmful to human respiratory system, but also harmful to human health because of the existence of pores that will adhere to toxic substances such as SO2, unburned HC and NO2 or carcinogens such as benzopyrene. Because the particle diameter of diesel engine is mostly less than 0.3 micron, the number is 30-60 times higher than that of gasoline engine, and the composition is more complex, so the particle emission of diesel engine is relatively greater.