What color is acid rain measured by ph test paper?

First, the number one air pollution-sulfur dioxide red

The atmosphere is the material on which we human beings live. An adult breathes more than 20,000 times a day on average, and the amount of air inhaled is 1.2 ~ 1.6 liters, which is 0/0 times of the daily food quality.

People can't live without the use of fuel in their daily life and production practice. At present, the two pillars of energy are coal and oil. There are many combustion products in coal and oil, but sulfur dioxide is one of the serious air pollution. Sulfur dioxide is a colorless and irritating gas, which is the most abundant, widely distributed and most harmful pollutant in the atmosphere.

Sulfur dioxide discharged into the air takes floating dust as the "carrier", which enters the respiratory tract with people's breathing, destroying the barrier function of the respiratory tract, weakening people's resistance, easily catching a cold, causing chronic bronchitis and tracheitis, and even causing emphysema in severe cases. After sulfur dioxide enters the blood through alveoli, it combines with vitamin B 1, which makes the balance of vitamin C unbalanced, thus destroying the activity of enzymes and affecting the new metabolism in human body.

Second, pollution accidents caused by sulfur dioxide

Mas Valley Smog Event-From February 0 to 5, 65438+65438, 0930, the iron sulfide smelter and coking plant in Belgium Valley Industrial Zone discharged a large amount of sulfur dioxide, fluorinated hydrocarbons and dust during production, which seriously polluted the atmosphere, causing thousands of people to suffer from respiratory diseases and acute poisoning when encountering inversion weather, and about 60 people died.

Donola Smoke Event-1948101October 26th ~ 3rd1day, in Donola Town, Pennsylvania, USA, harmful gases and dust such as sulfur dioxide emitted by zinc smelters, steel mills and sulfuric acid plants accumulated in the popularity of deep valleys, and could not spread, so they encountered unfavorable temperature and foggy weather. As a result, 43% of local residents were killed by about 6000 in four days.

In four days-1961year, the factory in yangshi, Japan discharged sulfur dioxide and coal dust into the atmosphere, inhaled into the lungs, and caused asthma, with more than 500 patients and 36 deaths. By 1972, there were 6370 patients.

This shows that the harm caused by sulfur dioxide is great, and it is urgent to solve such problems.

Third, the harm of acid rain.

Under the action of iron oxide in coal dust, sulfur dioxide is converted into sulfur trioxide and then into sulfuric acid mist. At this time, its harmful effect is 0/0 times of the original/kloc-0. The next rain will fall with the rain and form acid rain, which will not only directly harm people's health, but also acidify the soil, lead to crop reduction, forest destruction and corrosion of various equipment in buildings and factories.

According to the monitoring, the atmospheric acid rain pollution in Chengdu is becoming more and more serious, and the frequency of acid rain has increased from 15% 10 years ago to 3 1%. At present, southwest China has become the third largest acid rain area in the world after acid rain in Europe and North America. Although the research on acid rain in China has been nearly 20 years, the research level is far from enough. Domestic investment in acid rain research is less than that in Europe 1%, and the total number, density and monitoring items of monitoring points are much less than those in Europe and America.

Acid rain will corrode buildings and metals. The exquisite reliefs on the railings of the Forbidden City in Beijing, whose patterns were still legible more than 50 years ago, are mostly blurred now, and some of them have been corroded into light plates. Athens, a famous historical city, originally preserved many metal and stone statues left over from ancient Greece. In the past 10 years, they have been corroded. Acid rain corrodes railway tracks and shortens their service life. According to statistics, the global acid rain corrosion loss is as high as 654.38+0.8 billion dollars.

Acid rain acidifies rivers and lakes, affecting the survival of fish; Forests have fallen sharply and crops have been reduced. The acidification of lakes in Sweden 15000 seriously damaged aquatic animals and plants. In the Adirondack Mountains in the eastern United States, more than half of the lakes with an altitude of more than 700 meters have a PH below 5.0, and more than 90% have no fish. In northern Italy, acid rain is a disaster, and 5% of forests (equivalent to 9000 hectares) have died of acid rain. Sometimes hundreds of acres of crops will be burnt after acid rain. The most serious acid rain area in Europe is the border area between Czech Republic and Poland, where the PH value of acid rain dropped to 3.8, and trees died in 400,000 hectares of forest land in Lodz, Klocko Province. There are also 654.38+0.4 million hectares of spruce dead or on the verge of death in the border area between Germany and Czech Republic. The German Forest Union estimates that the timber industry loses $800 million a year.

Four. Measurement of PH value of rainwater

Under natural conditions, rainwater is also slightly acidic. The reason is that sulfur dioxide in the atmosphere is dissolved in pure rain, which makes the rain slightly acidic, and the general pH value is ≥ 5.6. However, if the atmosphere is polluted by acidic substances, the PH value of rainwater will further decrease, and the stronger the acidity, the smaller the PH value. Rain with PH less than 5.6 is called acid rain. The data in 5.6 comes from the acidity when distilled water and sulfur dioxide in the atmosphere reach the dissolution equilibrium.

The main steps of rainwater acidity measurement:

Collect rainwater samples

Prepare one or several containers, rinse them with distilled water for 2∽3 times, and then seal them for later use. On rainy days, put the container in a place where rainwater can be received and collect rainwater samples. The outer wall of the container containing rainwater samples is marked with the time and place of sample collection.

Measure the PH value of rainwater.

Measuring PH value with PH test paper: Dip a small amount of rainwater in a clean glass rod and put it on the PH test paper. Due to the different acidity of rain, the color of test paper is also different. By comparing with the standard color on the color plate, the PH value of rainwater can be roughly seen, and the PH value of each rainwater sample can be recorded.

data processing

The PH values measured by each rain sample are sorted by time, and the PH value diagram of time jujube is drawn.

5. Corrosion of buildings by acid rain.

When the mixed gas containing SO2, SO3 and water vapor in the air comes into contact with the concrete structure, the mixed gas diffuses from the outer surface of the concrete to the inner surface of the concrete through micropores, is absorbed by the inner surface, and undergoes chemical reaction to generate gypsum. The main reaction equation is: SO2+H2O = H2SO4,

2H2SO3+O2=2H2SO4，H2SO4+CaCl2=CaSO4+2HCl，

After gypsum is produced, the volume of gypsum will expand, while reinforced concrete will generally shrink. Due to the continuous expansion of gypsum, the coarse micropore structure continues to expand, which provides a more convenient way for the later gas mixture of SO2, SO3 and water vapor to invade. /FONT & gt； Broad? /FONT & gt； The mixed gas containing pollutants further diffuses into the concrete and reacts. Year after year, day after day, concrete cracks, resulting in weakening strength, thus destroying buildings.

Prevention and control of the harm of intransitive verbs

Recently, the United States and Japan are studying Na2SO3 absorption as a new method to control SO2 pollution. The first step is to absorb SO2 with Na2SO3 aqueous solution, and the second step is to heat the absorption solution to regenerate Na2SO3, and at the same time, obtain the water vapor by-product with high concentration of SO2.

Other basic measures are as follows:

Reduce the emission of sulfur dioxide. Using flue gas desulfurization technology, lime slurry or limestone is used for desulfurization in the flue gas absorption tower, so that SO2 is converted into Ca(HSO3 )2 and CaSO3, and finally oxidized into CaSO4.

Adjust the structure of civil fuel to realize fuel gasification. Use hydrogen as fuel. The calorific value of hydrogen combustion is as high as 120802KJ/Kg, which is three times that of gasoline. When burning, it can produce a high temperature of about 1700 degrees Celsius. Hydrogen is recycled into water after combustion, which is very clean, so it can also be called "pollution-free" energy. The source of hydrogen is common water, and oxygen and hydrogen can be obtained by water decomposition. Hydrogen needs oxygen for combustion, and then produces water.