The substance made of two or more different elements that have chemically combined is called a compound.

Here's why:

* Elements are the simplest pure substances that cannot be broken down further by chemical means. Examples include carbon, oxygen, and hydrogen.

* Compounds are formed when two or more elements chemically react and bond together in a fixed ratio. These bonds create a new substance with properties distinct from the original elements. Examples include water (H₂O), salt (NaCl), and carbon dioxide (CO₂).

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