Positive ions, also known as cations, are atoms or molecules that have lost one or more electrons, resulting in a net positive charge. This loss of negatively charged electrons can occur through various processes, such as chemical reactions or exposure to energy sources like heat or light. Common examples of positive ions include sodium ions Na+ and calcium ions Ca2+. In nature, positive ions play essential roles in various processes, including electrical conductivity in solutions and biological functions in living organisms. For instance, potassium ions K+ are crucial for nerve signal transmission in animals. Understanding positive ions is important in fields like chemistry, biology, and environmental science.