Which chemical element has the Atomic Number 4 and is the first of the Alkaline Earth metals?
Alkaline earth metal reactions to exchange ligands. Calcium, strontium, and barium all form octacarbonyl complexes and an 18-electron valence shell. The compounds were characterized in frozen neon matrices by vibrational spectroscopy and in gas phase by mass spectrometry. Analysis of the electronic structure reveals that not only barium but also strontium and calcium may effectively use their ("n" − 1)d atomic orbitals in chemical bonding, suggesting their behave like transition metals. The table below is a summary of the key physical and atomic properties of the alkaline earth metals. Of the six alkaline earth metals, beryllium, calcium, barium, and radium have at least
Chemical element Chemical element A chemical element is a species of atoms having the same number of protons in their atomic nuclei (that is, the same atomic number, or "Z"). For example, the atomic number of oxygen is 8, so the element oxygen consists of all atoms which have exactly 8 protons. 118 elements have been identified, of which the first 94 occur naturally on Earth with the remaining 24 being synthetic elements. There are 80 elements that have at least one stable isotope and 38 that have exclusively radionuclides, which decay over time into other elements. Iron is the most abundant