Which of the following is the smallest unit of an element that still retains the chemical properties of that element?

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

Answer: (B)

Verified step by step guidance

1. Understand the question is asking for the smallest unit of an element that retains its chemical properties.
2. Recall that an electron is a subatomic particle with a negative charge, but it does not represent the element itself.
3. Recognize that a proton is a positively charged subatomic particle found in the nucleus, which helps define the element but alone does not retain chemical properties.
4. Know that a molecule is a group of atoms bonded together and can be made of one or more elements, so it is not the smallest unit of a single element.
5. Identify that an atom is the smallest unit of an element that retains all the chemical properties of that element, as it contains protons, neutrons, and electrons arranged in a way that defines the element's behavior.