Understand the structure of a neutral sodium atom: A neutral sodium atom has 11 protons and 11 electrons, which balance each other out, resulting in no overall charge.
Recall the definition of ions: An ion is an atom or molecule that has gained or lost one or more electrons, resulting in a net charge.
Identify the process of ion formation for sodium: When a sodium atom loses an electron, it has more protons (11) than electrons (10), resulting in a net positive charge.
Recognize the charge of a sodium ion: Since the sodium atom has lost one electron, it becomes a sodium ion (Na⁺) with a positive charge.
Conclude why Na⁺ is positively charged: The loss of an electron, not the gain or loss of protons, is responsible for the positive charge of the sodium ion.