Atom

An atom is the smallest unit retaining the chemical properties of an element. It consists of a central nucleus with protons and neutrons, surrounded by electrons. Atoms of the same element have the same number of protons.

What is the smallest unit that retains the chemical properties of an element?

• Molecule

• Ion

• Atom

• Compound

What is found at the center of an atom?

• Neutrons

• Protons

• Electrons

• Nucleus

Which particles are found in the nucleus of an atom?

• Protons and neutrons

• Protons and electrons

• Electrons and protons

• Neutrons and electrons

What surrounds the nucleus of an atom?

• Ions

• Electrons

• Neutrons

• Protons

What is the defining characteristic of atoms of the same element?

• Same number of neutrons

• Same number of electrons

• Same atomic mass

• Same number of protons