Which statement best describes an atom?

Which statement best describes an atom?

• A. A group of atoms bonded together
• B. The smallest particle of an element
• C. A positively charged particle
• D. The nucleus only

Answer: (B)

An atom is the smallest unit that still has the properties of an element. That idea underpins why the statement about being the smallest particle of an element is the best description. A group of atoms bonded together is a molecule, which is larger than a single atom and not the fundamental unit of the element. A positively charged particle points to a proton, which is only a part of the atom and not the whole thing. The nucleus is just the center; the atom includes electrons around it too. So the atom isn’t just the nucleus or a proton, and it isn’t a cluster of atoms, but the smallest unit that defines the element.

An atom is the smallest unit that still has the properties of an element. That idea underpins why the statement about being the smallest particle of an element is the best description. A group of atoms bonded together is a molecule, which is larger than a single atom and not the fundamental unit of the element. A positively charged particle points to a proton, which is only a part of the atom and not the whole thing. The nucleus is just the center; the atom includes electrons around it too. So the atom isn’t just the nucleus or a proton, and it isn’t a cluster of atoms, but the smallest unit that defines the element.