In our life, there is the shadow of chemistry almost everywhere. First of all, we can't do without chemistry. For the simplest example, when people eat and drink water, chemical reactions will inevitably occur in every process, from food entering the test tube and stomach, to being digested by gastric acid, absorbed by capillaries and finally excreted. Besides, people eat food because it is nutritious, and where does nutrition come from? Plants are exposed to sunlight, and then through photosynthesis, water and inorganic salts become starch and are stored in grains. Today, when grain grows from the ground, nutrient solution and fertilizer are essential. The use of various nitrogen fertilizers, phosphate fertilizers, potash fertilizers and compound fertilizers has improved the yield and quality of grain. Pesticides are also essential in pest season. Coupled with the drugs that people use to treat diseases, these are the benefits that chemistry brings to mankind. Some common sense in life is also closely related to chemistry. For example, eating fruit can relieve alcohol. This is because fruit contains organic acids, and the main component of wine is ethanol, and organic acids can interact with ethanol to form esters, thus achieving the purpose of hangover. Also, when you open the bottle of carbonated drinks, bubbles will come out. The reason is that people often make soda water with baking soda (sodium bicarbonate) and citric acid. When baking soda and citric acid are mixed in water, they will react with each other to produce carbon dioxide gas, but the bottle has been blocked and carbon dioxide is forced to stay in the water. When the cork is opened, the external pressure is small, and carbon dioxide gas escapes from the water, forming a scene of bubbles churning.