Which statement correctly describes the force that holds atoms together?

• A. the electrostatic force of attraction between the protons in the nucleus and the surrounding electrons.
• B. the gravitational force between the nucleus and the electrons.
• C. the strong nuclear force between protons and neutrons.
• D. the magnetic force between charged particles in the electron cloud.

Answer: (A)

The binding of atoms is primarily due to the electrostatic (Coulomb) attraction between the negatively charged electrons and the positively charged protons in the nucleus. This electric attraction pulls electrons toward the nucleus and keeps them in orbit or bound in the electron cloud, giving atoms their structure and chemistry. On atomic scales, gravity is utterly negligible, and the strong nuclear force acts only inside the nucleus to hold protons and neutrons together—not to bind electrons to the nucleus. Magnetic forces can affect energy levels but are not the main cause of the atom’s overall binding. So the electrostatic attraction between the nucleus and the electrons is the correct description of what holds atoms together.