Final answer:
A positive ion formed by the loss of electrons is called a cation. Sodium becomes Na+, while calcium becomes Ca2+, both examples of cations, which play critical roles in various chemical processes and biological functions.
Step-by-step explanation:
The ion that is positive and defined by a deficit of electrons, a condition resulting from electron loss, is called a cation. Atoms become cations through the process of losing one or more of their electrons, resulting in a scenario where there are more protons, which are positively charged, than electrons, which are negatively charged. For instance, the element sodium (Na) can lose one electron to become Na+, a cation with a positive charge. In a similar fashion, calcium (Ca) can lose two electrons to form Ca2+, another example of a cation.
This formation of cations is a fundamental aspect of chemical reactions and is pivotal in various fields, including biology where elements like potassium (K) participate in vital bodily functions. In essence, when atoms become electrically charged due to an imbalance in proton and electron counts, we refer to them as ions. The positive ions, or cations, migrate towards the negative electrode, also known as the cathode, when placed in an electrical field.