What are substances made of?

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Explanation: A chemical substance is composed of one type of atom or molecule. A mixture is composed of different types of atoms or molecules that are not chemically bonded. A heterogeneous mixture is a mixture of two or more chemical substances where the various components can be visually distinguished.

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A substance is simply a pure form of matter. In other words, a substance is matter than contains only one type of atom or molecule.

here's your answer>  A chemical substance is composed of one type of atom or molecule. A mixture is composed of different types of atoms or molecules that are not chemically bonded

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.Pure substances are substances that are made up of only one kind of particles and has a fixed or constant structure. Pure substances are further classified as elements and compounds. An element is a substance that consists of only one type or kind of atom.

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a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements