* Elements: Brass is made up of two elements: copper (Cu) and zinc (Zn).

* Chemical Bonding: The elements in brass are not chemically bonded together to form a new substance. They are physically mixed.

* Variable Composition: The ratio of copper and zinc in brass can vary, depending on the desired properties of the final product.

In contrast, a compound would involve a fixed ratio of elements chemically bonded together, resulting in a new substance with different properties from the original elements.