A substance made of two or more substances chemically bonded together is called a compound.

Here's why:

* Chemical bonds involve the sharing or transfer of electrons between atoms. This creates a new substance with properties different from the original elements.

* Mixtures, on the other hand, are simply combinations of substances that are not chemically bonded. They can be separated by physical means.

Examples of compounds:

* Water (H₂O) - made of hydrogen and oxygen

* Salt (NaCl) - made of sodium and chlorine

* Sugar (C₁₂H₂₂O₁₁) - made of carbon, hydrogen, and oxygen

Let me know if you have any other questions!