Question

an atom has no electrical charge because ____.
○ the number of protons is equal to the number of neutrons
○ the number of neutrons is equal to the number of electrons
○ the number of protons is equal to the number of electrons
○ all of these

Explanation:

In an atom, protons have a positive charge, electrons have a negative charge, and neutrons have no charge. For an atom to be electrically neutral (have no net charge), the positive charge from protons must balance the negative charge from electrons. So the number of protons (positive charge carriers) must equal the number of electrons (negative charge carriers). Neutrons don't contribute to charge, so their number relative to protons or electrons doesn't affect the atom's electrical neutrality. Thus, the correct reason is that the number of protons equals the number of electrons.

Answer:

C. the number of protons is equal to the number of electrons