Which of the following is the basic unit of matter and is the smallest particle of an element that retains its chemical properties?

• A. Proton
• B. Molecule
• C. Atom
• D. Electron

Answer: (C)

Verified step by step guidance

1. Understand the question is asking for the smallest particle of an element that retains its chemical properties.
2. Recall that a proton is a subatomic particle found in the nucleus of an atom, but it alone does not represent the entire element.
3. Recognize that an electron is a subatomic particle with a negative charge orbiting the nucleus, but it also does not represent the whole element.
4. Know that a molecule is made up of two or more atoms bonded together, so it is not the smallest unit of an element.
5. Conclude that the atom is the basic unit of matter and the smallest particle of an element that retains its chemical properties.