alkaline earth metals chemical properties
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Alkaline earth metals are the six elements forming Group IIa in the Periodic Table: beryllium (Be), magnesium (Mg), Calcium (Ca), Barium (Ba), Strontium (Sr), and Radium (Ra)âœ¶. Their oxides are basic (alkaline), especially when combined with water. "Earth" is a historical term applied to nonmetallic substances that are insoluble in water and stable to heating, and also the properties of the oxides. Hence, the term "alkali earths" is often used to describe these elements. âœ¶ See Periodic Table in the For Your Reference section of Volume 1. Each metal has the electron configuration of an inert (noble) gas plus two electrons in the next higher s orbital. Thus, Mg is 1s 22s 22p 63s 2 or alternatively (Ne)3s 2. The bonds of most compounds of alkali earths are ionic in nature because these outermost electrons are readily lost, forming stable divalent cations. Mg, however, can form compounds with both ionic and covalent bonds , whereas most compounds of Be are covalent. The heavier alkali earths are sometimes compared to Group IIb elements (zinc [Zn], cadmium [Cd], mercury [Hg]) that also have a filled s orbital (5s 2), but the filled 4d 10 orbitals and higher ionization energies of the latter make compounds of Group IIb elements markedly less ionic in character than those of alkali earths. Mg and Ca are the eighth and sixth most abundant elements in Earth's crust at 2.5 and 3.6 percent, respectively. Be, Sr, and Ba comprise 0.001, 0.025, and 0.05 percent, respectively. Ra is radioactive, and since its longest-lived isotope 226Ra has a half-life of 1,600 years, there is very little Ra in Earth's crust. It is nonetheless present because 226Ra is continuously formed by the decay of uranium (238U). Alkali earth elements are very reactive and strongly reducing in character; thus, none occurs in a free state in the environment. They readily react with oxygen, and the pure metals tarnish in air, forming a surface layer of the oxide. The metals are soluble in liquid ammonia, forming covalent compounds with the general formula M(NH3)6. These solutions are strongly basic and frequently find application in industry. Oxides of alkali earths were known in ancient times, calcium oxide being lime (from the Latin word calx ). Magnesium oxide or magnesia was also known, its name probably deriving from a district in Asia Minor. Oxides of the other alkali earths were identified in the eighteenth century. Barium oxide or baryta was found in the mineral called heavy spar and given the name barys (from the Greek, meaning "heavy"). Strontia or strontianite (strontium carbonate) was found in a lead mine at Strontian in Scotland. Beryllium oxide was extracted from the mineral beryl (from the Greek word bÃ¨ryllos ). Be was originally called glucina (from the Greek glykys, meaning "sweet") because of its taste and is sometimes still referred to as glucinum in France. The English chemist Sir Humphry Davy first isolated Mg, Ca, Sr, and Ba in 1808 by means of electrolysis. (Mg was originally called magnium since Davy had already applied the word "magnesium" to the element manganese.) Be was initially isolated from beryl by the French chemist Antoine Bussy and independently in Germany by Friedrich WÃ¶hler in 1828. The discovery of Ra did not occur until 1898 when Marie and Pierre Curie purified it from barium using its radioactivity. They named it from the Latin word radius (meaning "ray") because the strength of its radioactivity was more than a million times that of uranium. Because of their metallic properties and low mass, Be and Mg are used to form lightweight alloys for structural purposes. Ca sees less industrial use, although the phosphate is sometimes utilized in fertilizers. Sr and Ba have no significant industrial applications. Both Be and Ra are used in various devices, the former because it is quite transparent to x-rays and the latter because it is a ready source of both Î± - and Î³ -radiation. Mg and Ca are essential to all living systems for many reasons; the other alkali earths have no known biological roles. see also Beryllium; Cesium; Curie, Marie Sklodowska; Davy, Humphry; Francium; Magnesium; Potassium; Rubidium; WÃ–hler, Friedrich. Michael E. Maguire Nechaev, I.; Jenkins, G. W.; and Van Loon, Borin (1997). Chemical Elements: The Exciting Story of Their Discovery and of the Great Scientists Who Found Them. Jersey City, NJ: Parkwest Publications. Rossotti, Hazel (1998). Diverse Atoms: Profiles of the Chemical Elements. New York: Oxford University Press. Winter, Mark (2003). WebElements Periodic Table, Scholar Edition. WebElementsLtd. Additional information available from
alkaline-earth metals metals constituting Group 2 of the periodic table . Generally, they are softer than most other metals, react readily with water (especially when heated), and are powerful reducing agents, but they are exceeded in each of these properties by the corresponding alkali metal. They form divalent compounds. In order of increasing atomic number the alkaline-earth metals are beryllium , magnesium , calcium , strontium , barium , and radium .
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Answers:They are soft can be cut by a knife React with air and water(even cold water) Shiny metals Form soluble salt by reacting with halogens(group 7 metals)
Answers:Alkali metals need to lose one electron to have full shells, alkali earth metals need to lose two. They bond ionically and are highly reactive, heavier alkali metals being the most reactive because the outer electrons are furthest from the nucleus so least affected by the electromagnetic forces holding the atom together.
Answers:alkaline earth metals are those belonging group 2 of the periodic table.The alkaline earth metals are named after their oxides, the alkaline earths, whose old-fashioned names were beryllium, magnesia, lime, strontia and baryta. These oxides are basic (alkaline) when combined with water. "Earth" is an old term applied by early chemists to nonmetallic substances that are insoluble in water and resistant to heating--properties shared by these oxides. Hence, the term "alkaline earth" is often used to describe these elements. the elements include beryllium, magnesium, calcium, radium, strontium and barium.they share similar chemical and physical properties.like they are all soft metals having low density.they also tend to rapidly react with water to form basic hydroxides like Ca(OH)2.they can be identified using flame test as they impart characteristic colour to flame.example Ca gives red colour,Be gives green and so on.except for a few anomalies their behaviour can be predicted.
Answers:The Alkaline Earth Metals are called that because: 1. They are alkaline. That is they make compounds that are caustic, which is what alkaline means. We get caustic or alkaline earth metals from the ash of fires and from the minerals in the earth. 2. Which leads to the next part of the name. They are Earth Metals. That means that they are found in soils around the earth. The most common place to find an Alkaline Earth Metal is in Limestone, which is a compound of Calcium with some Magnesium in it. Both Calcium and Magnesium are in Limestone. But they are also found in hard water and in the bones of our bodies. 3. Finally they are Metals. That means that they become positive charged by losing electrons in chemical reactions. They all lose two electrons in all chemical reactions, so they act in very similar fashion with all Alkaline Earth Metals. There are other things you could go into. The lighter weight the Alkaline Earth Metals are the harder they are. For example Magnesium metal is often used in light weight bikes used by professional bikers like Lance Armstrong or by backpackers who climb mountains. When I was younger and hiked over 1,200 miles in the High Sierras, I used a backpack with a frame made from Magnesium. Beryllium, the lightest of all of the Alkaline Earth Metals is often alloyed with other metals to reduce the amount of sparks that the metal might cause. That allows the alloys to be used in places where fires can cause a lot of trouble, such as in oil refineries.