Take daily life as an example. If you don't have some chemical knowledge, you may take a lot of detours or bring yourself a lot of inconvenience.
Taking medicine and drinking water is a familiar thing for everyone. But some people take it for granted that they must invent the method of drinking tea and taking medicine. There seems to be nothing wrong, but it is not. Tea contains a substance called manic acid, which can react with protein, alkaloids, heavy metal salts and other substances in drugs to produce precipitation, which not only affects the curative effect of drugs, but also produces some side effects. Therefore, pepsin, iron fumarate and other drugs can not be taken with tea. Tea also contains caffeine, theophylline and other ingredients, which can excite nerves, so it is not easy to take tea when taking central nervous system inhibitors.
Another example is boiler water. The water used for steaming steamed bread or side dishes at home is called boiler water. This kind of water can't be drunk, nor can it be used for cooking rice or porridge. What is the reason? The water in the steamer contains a little nitrate. When water is heated for a long time, the nitrate concentration increases relatively and becomes nitrite after being decomposed by heat. Nitrite is very harmful to human health, which can denature hemoglobin in human blood and can no longer combine with oxygen. Nitrite can also reduce human blood pressure, which can lead to collapse in severe cases.
China is a big smoker, and most men and a few women smoke in our country. As we all know, smoking addiction does harm to smoking. However, many people don't know that he is more harmful to non-smokers. There are two kinds of cigarettes: mainstream cigarettes and non-mainstream cigarettes. Mainstream cigarettes are inhaled by smokers and non-mainstream cigarettes are inhaled by passive smokers. Non-mainstream tobacco is formed by incomplete combustion of tobacco, which is dirtier than mainstream tobacco and has different chemical composition. People who died of passive smoking mainly died of lung cancer and heart disease. Non-smokers living with smokers have a 30% increased risk of dying of heart disease. For children whose parents smoke, blood tests show that their blood cholesterol is high and their high-density lipoprotein level, which can prevent heart disease, is low, which increases the risk of heart disease.
There are many such examples. If you don't know the relevant chemical knowledge, you will definitely be in trouble.
Chemistry not only plays an important role in our daily life, but also can improve our life.
A number of scientific research institutions in Germany recently announced the successful cooperation in developing solar cells with ordinary organic polymers as the core. The researchers found that when polymer plastic ions are irradiated by sunlight, the electronic vibration of carbon atoms on their surfaces is obviously accelerated and the amplitude is increased, but the speed of returning to the carbon atom orbit is much slower, thus forming an "electron-hole" in a few subtle times. In order to make it form an electric current, the researchers made a "sandwich" with aluminum on one side and zinc indium metal oxide on the other, and plastic ions filled in the middle. Such a sandwich itself has an electric field between the two layers, and polymer plastic ions play the role of insulating layer. However, under the irradiation of sunlight, due to the "electron-hole pair" generated by carbon atoms of polymerized organic matter, negatively charged electrons flow to the aluminum metal layer, and positively charged "hole" zinc indium metal oxide layer flows, resulting in current. Although the popularization of solar cells still has a long way to go, its use will promote the utilization of solar energy. We can't help thanking chemistry here.
Of course, while benefiting mankind, we have also caused great damage to the environment. Many problems in the environment can be explained by chemical knowledge.
The word "greenhouse effect" is no stranger to us, and because of the intensification of the greenhouse effect, the word has been hanging on people's lips more and more. How is the greenhouse effect intensified? This also needs the help of chemical knowledge to explain. Carbon dioxide and water vapor in the earth's atmosphere allow a part of solar radiation (short-wave radiation) to reach the ground through the atmosphere, and it can also absorb long-wave radiation emitted by the sun and the earth's surface, so that only a small part of thermal radiation is dissipated into space. Because the atmosphere gains more heat than it loses, the earth keeps a relatively stable temperature, which is the so-called greenhouse effect. He played a protective role in life on the earth. However, due to the population explosion, the surge of human activities, the sharp increase of chemical fuel burning, and the sharp decrease of deforestation, the content of carbon dioxide and various gas particles in the atmosphere is increasing, which leads to the increase of long-wave radiation absorbed and reflected back to the ground, which leads to the increase of the surface temperature of the earth, the intensification of greenhouse effect and the warming of the climate. Therefore, the increase of carbon dioxide is considered as the main cause of air pollution. I don't think it is necessary to say more about the harm brought to us by the intensification of the greenhouse effect. When we find problems through analysis, we can find solutions. In order to slow down the intensification of the greenhouse effect, we must strive to reduce the use of fossil fuels and develop new energy sources, prohibit deforestation, and especially strictly control population growth.
The formation of big holes and red tides in the ozone layer of the North and South poles can also be explained by chemical knowledge.
In a word, let's go back to the original topic: chemistry is everywhere in our lives, whether it is daily life or daily necessities, or the environment we live in. We should not only learn chemistry knowledge in class, but more importantly, we should connect knowledge with life and discover chemistry around us.