Final answer:
The smallest piece of an element that maintains its properties is known as an atom. Atoms are incredibly small, yet they form all matter seen in the universe. An atom has a nucleus with protons and neutrons, and electrons orbit this nucleus.
Step-by-step explanation:
The smallest piece of an element (like gold or lead) that still has all the properties of that element is called: an atom. An atom is the fundamental unit of matter that defines the chemical elements. Each atom has a nucleus containing protons and neutrons, with electrons in the surrounding space. The atomic structure ensures that if you keep dividing material like gold, you eventually reach the smallest piece that still exhibits all the characteristic properties of gold; go smaller and these properties are lost.
An atom of gold is a solid metal at room temperature and represents the pure essence of the element. Atoms are so small that roughly fifty million atoms lined up would stretch for just one centimeter. Despite their tiny size, all matter is composed of atoms which come together to form molecules and larger structures that we interact with daily.