One of the important ways to learn chemistry is to recognize substances by classification A. Fresh air B. carbon dioxide C. mineral water D. clarified lime water

One of the important ways to learn chemistry is to recognize substances by classification A. Fresh air B. carbon dioxide C. mineral water D. clarified lime water

A. Fresh air contains nitrogen, oxygen and other substances, belonging to the mixture; B, carbon dioxide is composed of carbon dioxide, belonging to the pure substance; C, mineral water contains water, soluble minerals and other substances, belonging to the mixture; D, clear lime water contains water and calcium hydroxide, belonging to the mixture

Of the following substances, the one that is pure is ()
A. Soymilk B. alcohol C. vinegar D. milk

A. Soybean milk contains water, protein and other substances, which belong to the mixture. B. alcohol contains only one substance, which belongs to the pure substance. C. vinegar contains water, acetic acid and other substances, which belong to the mixture. D. milk contains water, protein and other substances, which belong to the mixture