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

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

Answer: (A)

Verified step by step guidance

1. Understand the question is asking for the smallest particle of an element that retains all its chemical properties.
2. Recall that an atom is the basic unit of an element that maintains its chemical identity and properties.
3. Recognize that a molecule is made of two or more atoms bonded together, so it is not the smallest particle of an element.
4. Note that a proton is a subatomic particle found inside the nucleus of an atom, but alone it does not retain the chemical properties of the element.
5. Similarly, an electron is a subatomic particle orbiting the nucleus and does not define the chemical properties of an element by itself.