A chemically formed substance by combining two or more elements is called a compound.

Here's why:

* Elements: Basic building blocks of matter that cannot be broken down further by chemical means (e.g., oxygen, carbon, hydrogen).

* Compound: A substance formed when two or more different elements are chemically bonded together in a fixed ratio. The resulting compound has properties that are different from the original elements (e.g., water (H₂O) is a compound formed from hydrogen and oxygen).

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