3. It's not a pure substance, () it is made of different substances.
举一反三
- The physical properties are those properties of a substance that can be observed with changing the substance into other substances.
- Which of the following substances is not amphoteric substance? A: H2O B: HCO3- C: H2PO4- D: CO32-
- Fats and fixed oils are greasy or waxy substance that ill their pure state are normally tasteless, colorless, and odorless.（） A: or B: substance C: their D: normally
- A pure substance always has the same physical and chemical properties and is either an element or a compound.。（ ）
- Which of the following () may not be interested in science and technology A: The substance facing a resource shortage B: The substance with an increasing uses C: The substance whose anthropogenic flow is closely related to other substances D: None of the above