Kaplan Nursing Entrance Practice Exam

What happens to an atom when it becomes an ion with a positive charge?

1. It gains a neutron

2. It loses a proton

3. It gains an electron

4. It loses an electron

The correct answer is: It loses an electron

When an atom becomes an ion with a positive charge, it loses an electron. This process involves the atom having more protons than electrons in its structure, which results in a net positive charge. Atoms are defined by their number of protons, neutrons, and electrons. The protons, located in the nucleus, contribute to the atomic number and thus define the element itself. Electrons orbit the nucleus and their number typically matches the number of protons in a neutral atom, resulting in no overall charge. When an electron is lost, the balance between protons and electrons is disrupted; with more protons than electrons, the atom will have a positive charge, hence becoming a cation. In summary, the correct answer reflects the understanding that the loss of an electron leads to the formation of a positively charged ion. This fundamental concept is a key principle in both chemistry and physics, illustrating how atoms interact to achieve stability through charge changes.