Coral is a kind of marine coelenterate. The skeleton left by coral insects after death is coral, and its basic ingredient is calcium carbonate or pectin. Most of the red, pink, and white corals are composed of calcium carbonate, CaCO3, while the black and gold corals are composed of the horny substance of “isothetin”
And why is the color of red coral so red? The main reason is that the seawater encountered during the growth process is composed of iron oxide. Iron oxide determines the color of the coral. Therefore, the surface color of Akha coral is the darkest, and it has a white core after it is cut.
Coral has low hardness and has pores that are invisible to the naked eye. If it is not properly maintained, it will lose its luster, which is called “fogging” or “matte”.
The main component of coral is calcium carbonate, and the main components of human sweat are sodium chloride and water, potassium, calcium, urea, lactic acid and amino acids, etc., as well as iron, lipids (neutral fats, fatty acids, cholesterol and lipids) Quality), fluorescent substance, smelly substance.
When I was learning chemistry as a child, I learned the law of conservation of mass, including an experiment.
“CaCl2+Na2CO3à CaCO3+2NaCl”
Since calcium carbonate is hard to dissolve in water, it will form a white precipitate.
It is also on corals. Calcium carbonate is alkaline. Because the chemical substances in sweat (acidic substances) and corals with calcium carbonate (alkaline substances) produce chemical reactions, some people will have white deposits on the coral surface. This is normal. But no one tried to test the chemical composition of the white sediment on the coral.
