There is chemistry everywhere in life, and through learning, I already know the salt master as a fla

The main component of table salt is sodium chloride, so the answer is: NaCl;

Dry ice absorbs a lot of heat during sublimation, so that the ambient temperature is reduced, so it can be used for artificial rainfall, so the answer is: dry ice;

Activated carbon has adsorption properties, which can adsorb pigments, odors, and toxic gases, so the answer is: adsorption;

The hardest of the natural substances is diamond, so the answer is: diamond;

The soda ash solution is alkaline and can make the colorless phenolphthalein red, so the answer is: red;

Copper sulfate is a white solid, which turns blue when exposed to water to generate copper sulfate pentahydrate, which can be used to test whether gasoline is mixed with water, so the answer is: copper sulfate;

After mosquito bites, soapy water can be applied to relieve itching, because soapy water is alkaline, pH 7, and formic acid has a neutralizing reaction, so it can relieve itching, so the answer is: ;

The chemical formula of methane is CH4, and the mass fraction of carbon contained in methane is: 1212+4

100%═75%，