Difference between ca and ca2+
The Correct answer and Explanation is:
The key difference between Ca and Ca²⁺ lies in their electrical charge and electron configuration. Calcium (Ca) is a neutral atom with 20 protons and 20 electrons, whereas calcium ion (Ca²⁺) has lost two electrons, resulting in a positively charged ion with 20 protons and only 18 electrons.
Explanation:
- Calcium Atom (Ca): A neutral calcium atom has the atomic number 20, which means it has 20 protons in its nucleus and 20 electrons distributed across its electron shells. These electrons are arranged in energy levels: 2 in the first shell, 8 in the second, 8 in the third, and 2 in the outermost shell (also called the valence shell). The atom is electrically neutral because the number of positive protons equals the number of negative electrons. The presence of two electrons in the outermost shell makes calcium chemically reactive, as it tends to lose these electrons to achieve a stable electron configuration similar to noble gases.
- Calcium Ion (Ca²⁺): When calcium forms an ion, it loses two electrons from its outer shell. This loss of electrons results in a Ca²⁺ ion, which now has 20 protons but only 18 electrons. The positive charge (²⁺) indicates that the ion has two fewer electrons than protons, making it positively charged. Losing two electrons allows calcium to achieve a stable, noble-gas electron configuration (similar to argon), making Ca²⁺ more stable than the neutral atom in many chemical reactions. The process of losing electrons to form a cation is called ionization.
Chemical Behavior:
- Reactivity: Calcium (Ca) in its neutral form reacts with other elements, often metals and nonmetals, to form compounds by losing its two outermost electrons. On the other hand, Ca²⁺, being a stable ion, is commonly found in ionic compounds like calcium chloride (CaCl₂) or calcium carbonate (CaCO₃).