Why are atoms electrically neutral under normal conditions?

• A. Because the mass of protons cancels out the mass of electrons.
• B. Because atoms have no charged particles.
• C. Because atoms contain equal numbers of neutrons and electrons.
• D. Because the number of protons equals the number of electrons in an atom.

Answer: (D)

Verified step by step guidance

1. Understand that atoms are composed of three main subatomic particles: protons, neutrons, and electrons.
2. Recall that protons carry a positive charge, electrons carry a negative charge, and neutrons are electrically neutral.
3. Recognize that the overall electrical charge of an atom depends on the balance between the number of protons and electrons.
4. Note that under normal conditions, the number of protons (positive charges) is equal to the number of electrons (negative charges) in an atom.
5. Conclude that because the positive and negative charges are equal in magnitude but opposite in sign, they cancel each other out, making the atom electrically neutral.