Answer:
1. A chemical substance is a form of matter having constant chemical composition and characteristic properties.
2. Pure substances are mostly homogeneous in nature containing only one type of atoms or molecules.
3. A substance that has a fixed chemical composition throughout is called a pure substance such as water, air, and nitrogen.
Explanation:
sorry po, pero diko na po alam yung sa may baba. paki-brainlest na lang po ako. maraming salamat po, have a nice day.
