The process of processing fresh eggs into preserved eggs is a complex chemical process. Strong alkali (sodium hydroxide and potassium hydroxide) in the ash material permeates into the egg yolk and egg white from outside the eggshell, and reacts with protein in the egg yolk and egg white, so that protein decomposes, solidifies and releases a small amount of hydrogen sulfide gas. At the same time, the infiltrated alkali further reacts with the amino acids decomposed by protein, and the crystals of the generated salt condense into beautiful shapes in the egg white, like blossoming "pine flowers".
Hydrogen sulfide gas reacts with minerals in egg yolk and egg white to generate various sulfides, so the colors of egg yolk and egg white change. Egg yolk is dark green and egg white is special tea green. Salt can shrink preserved eggs from eggshells, increase flavor and prevent corrosion. The added lead can accelerate the ripening of preserved eggs and promote the shrinkage and shelling of preserved eggs. Tannin and aromatic oil in tea can solidify and color protein, and increase the flavor of preserved eggs.
2. The reason why the non-stick pan doesn't stick to food is because the bottom of the pan is coated with a special substance: "Teflon", whose chemical name is PTFE and its common name is Plastic King.
I feel sore all over after strenuous exercise. This is because lactic acid in my muscles has increased.
After the first frost, the taste of vegetables and radishes is sweet, because the starch in vegetables is hydrolyzed by enzymes in plants to produce glucose.
5. The original works of ancient calligraphers in China can be preserved to this day: ink or carbon ink is used to make the handwriting not fade for a long time, which is because the chemical properties of carbon are stable.
Extended data:
Key points of chemical knowledge in life?
First, about the burning of matter?
1. Light two candles with different heights and cover them with a beaker. The tall candle goes out first, because the generated carbon dioxide gas has a high temperature, rises and then fills the whole bottle from top to bottom. Therefore, when there is an indoor fire, cover your nose and mouth with a wet towel and bend down to escape from the fire. The way to escape from forest fire is to block your nose and mouth with a wet towel and escape against the wind?
In order to ensure safety, helium can be used to inflate the balloon during the celebration, but hydrogen can't be used.
Gas poisoning is caused by carbon monoxide. The effective way to prevent gas poisoning is to pay attention to ventilation. In order to prevent gas leakage, we often add mercaptan (C2H5SH) with special smell to the gas to understand the gas leakage. When gas leakage is found, open the doors and windows in time and close the gas valve. No lights, no phone calls, no electric fans, etc. Because of these behaviors, there will be sparks and gas explosions. ) When someone is found to be poisoned by gas, attention should be paid to moving the patient to a ventilated place for manual operation.
4. The candle blows out because the cold air lowers the temperature of the candle below the ignition point, and the fan fire is getting more and more prosperous because it provides enough oxygen and increases the contact area between coal and oxygen.
5. The gas used in the West-East Gas Transmission Project is natural gas, and its main component is methane. The main gas of coal mine gas explosion is methane. The reason is the poor ventilation in the mine, which leads to the explosion limit of methane mixed with air, which is ignited and then exploded. Therefore, in order to prevent coal mine explosion, we should always keep ventilation and forbid fireworks.
6. There is often a small amount of red phosphorus in the light bulb, mainly to remove the oxygen in the lamp?
7. In case of fire, block your nose and mouth with a wet towel to prevent inhalation of toxic gas. If toxic gases (including chlorine gas, hydrochloric acid, hydrogen sulfide and ammonia gas) leak, cover your nose and mouth with a wet towel, and then flee to higher ground.
Second, about food?
1. Fresh eggs can be kept fresh by putting them in limewater, because the carbon dioxide exhaled by eggs reacts with limewater to generate calcium carbonate, which blocks the micropores on the surface of eggs and prevents oxidative deterioration.
2. In order to prevent food from getting wet, deteriorating or deforming, food bags are often filled with carbon dioxide or nitrogen; Or put desiccant in the bag: quicklime and calcium chloride mainly absorb water, and iron mainly absorbs oxygen and water; Or vacuum packaging.
3. The main gases in swim bladder are carbon dioxide and oxygen.
4. Add some soda ash to the steamed bread, mainly to neutralize the acid generated during flour fermentation, and the generated carbon dioxide can make the bread loose and porous.
5. The residual pesticides in vegetables can be soaked in alkaline substances, which can reduce the medicinal properties of pesticides?
6. Can the astringency of preserved eggs be removed with vinegar?
7. The odor of refrigerator can be removed by activated carbon, that is, the adsorption of activated carbon is utilized.
8. Can the scale (mainly composed of calcium carbonate and magnesium hydroxide) on aluminum pot be removed with hydrochloric acid or vinegar?
Third, environmental problems?
1. Acid rain is caused by a large number of nitrogen oxides and sulfur oxides (such as SO2 and NO2). The hazards of acid rain include: corrosion of buildings, impact on crop growth, pollution of rivers, impact on human health and land acidification. Measures to reduce acid rain: open up new energy sources, use less coal as fuel and use coal desulfurization technology.
2. Automobile exhaust contains carbon monoxide, nitric oxide, sulfur dioxide, etc. The treatment methods are: changing the engine structure to make the fuel burn fully; A catalytic converter is installed on the exhaust pipe to convert CO and NO into nontoxic N2 and CO2. The methods to control automobile exhaust pollution in cities include: developing new energy sources; Use an electric car?
3, methods to prevent water pollution:
(1) Strengthen water quality monitoring?
(2) Industrial wastes should be treated before being discharged?
(3) Rational use of pesticides and fertilizers?
(4) Prohibit the use of phosphorus-containing washing powder?
(5) Strengthen soil and water conservation and plant trees?
Water saving methods: secondary utilization of water (washing rice and watering flowers), turning off tap, low irrigation technology and secondary utilization of industrial water.
4. Greenhouse effect?
Due to the use of coal and petroleum fuels, the content of carbon dioxide in the air is increasing. The adverse effects are: global warming, land desertification and melting of polar glaciers; The measures that can be taken are: planting trees and prohibiting deforestation; Reduce the burning of fossil fuels and make more use of solar energy, wind energy, geothermal energy, nuclear energy and hydropower.