Periodic table Alkaline earth metals definition chemistry

Essentially, the heavier the alkaline earth metal, the more vigorously it will react with water. All of the alkaline earth metals except beryllium and magnesium also react with water to produce hydrogen gas and their respective hydroxides (magnesium will react with steam, however). As a result, they are not found in nature in their elemental state.Īll but one of the alkaline earth metals react with the halogens ( chlorine, fluorine etc.) to form ionic compounds (beryllium chloride is the exception, because the bonding is covalent). Metallic bonds in the alkaline earth metals are thus stronger than for the alkali metals, resulting in higher melting points, but they are still quite reactive because the two outer electrons are easily lost. The term 'earth' is historical it was the generic name used by alchemists for the oxides of these elements (which at one time were thought to be elements in their own right).Īll of the elements of group two have two electrons in their outer shell. Generally, group 1 metal compounds are more soluble than any group 2 analogue. Like the alkali metals, they form alkaline solutions when they react with water. The solubility of many group 1 and 2 metal compounds have trends down the groups. The elements in this group, which are all shiny and silvery-white in appearance, are known as the alkaline earth metals. Group two of the periodic table comprises the elements beryllium, magnesium, calcium, strontium, barium and radium. See also: alkali metal, halogen, inert, water reactive.Īdditional definitions from Google and OneLook.The alkali metals (highlighted) occupy group one in the periodic table The Physics and Chemistry of Beryllium (PDF file) at Brush Wellman, a major beryllium supplier.Department of Energy has a Former Worker Medical Screening Program for those who may have been exposed to hazardous or radioactive substances while working on government projects. 2023 discusses technical, organizational, and personal safety measures to comply with worker protection legislation and to ensure safe work with beryllium and its compounds. Handling Beryllium, the Safe Way in ACS Chem.Public Health Statement on Beryllium at the US Agency for Toxic Substances and Disease Registry.The EPA also has a Berylium fact sheet for consumers (archived) which focuses on drinking and ground water.Environmental Protection Agency has a highly technical summary of beryllium uses and toxicity. More info and pictures for calcium and other elements at WebElements.

The Alkaline Earth Metals (Group 2) at Chemistry LibreTexts™.See the notes under alkali metals for more info. The other alkali metals are all flammable and water reactive, so special care needs to be taken in using these and a proper Class D extinguisher should be available.Įlemental Mg, Ca, Ba and Sr are incompatible with certain classes of chemicals such as halogenated solvents. See the links below for further information. An interactive Periodic table can be found Periodic Table of the Elements, LibreTexts. The semimetals lie along a diagonal line separating the metals and nonmetals. The metals are on the bottom left in the periodic table, and the nonmetals are at the top right. These will depend on the specific alkaline earth and its form.īeryllium is toxic in both the elemental form and in salts/compounds as Be 2+, so special precautions such as respirators need to be used whenever dusts or fumes of Be or its compounds can be released. 1: The Periodic Table Showing the Elements in Order of Increasing Z. The Safety Data Sheet for a material will contain vital information concerning the hazards of the material. Hazards often depend on the chemical state of the material! SDS Relevance Note that there is a great difference between an alkaline earth metal (such as Ca) and an alkaline earth cation (such as Ca 2+). Calcium barium, and strontium should be stored under an inert atmosphere and/or mineral oil. In some cases, the heat of this reaction can ignite the hydrogen gas (H 2) that is evolved in the reaction.Īlthough these metals are shiny when cut, they tend to tarnish in air.

The reaction of elemental Ca, Sr and Ba with water can be summarized by the chemical equation below where M = an alkaline earth metal. First and second ionization energies for the alkaline earths (corresponding to removal of the first and second valence electrons) are relatively small, but the disruption of an octet by removal of a third electron is far more difficult. This reactivity increases as one moves down the column from Ca to Ba. 1: Properties of the Group IIA Alkaline-Earth Metals. Get your Class D and other specialty extinguishers from Safety Emporium.Ĭa, Sr and Ba are reactive towards air and water in their elemental (metal) form, but much less so than their alkali metal counterparts.

Periodic table Alkaline earth metals definition chemistry