Alkaline earth metals chemical reactivity

In addition to having similar electron configurations, some blocks have common chemical characteristics, too. The block of elements on the far left of the illustration, for example, are all metals. The two groups in the block are called the alkali metals (first column) and alkaline earth metals (second column). The alkali metals are remarkably similar soft, silvery, highly reactive metals. The alkaline earth metals form another distinctive group that are much harder that the alkaline metals and have higher melting points. 

Lithium metal is highly reactive but less so than other alkah metals. Its chemical properties, however, are more like those of the alkaline earth metals. 

Common chemical properties The alkali metals are so chemically reactive that they are never found free in nature. Sodium and potassium react explosively with water to produce hydrogen gas. The alkaline earth metals are not quite as reactive as the alkali metals. The alkali metals react with water but not explosively. The transition metals are generally the least reactive of all the metals. However, when they combine with other elements, they form a large variety of colored compounds. Chromium oxide is green, titanium oxide and zinc oxide are white, manganese oxide is purple, and iron oxide is ochre. 

Though not as chemically reactive as the alkali metals, the alkaline earth metals lose or share two outermost electrons easily to obtain eight outermost electrons. Calcium (Ca) reacts with hydrogen gas (H2) to produce calcium hydride (CaH2), and with water (H20) to produce calcium (Ca2+), hydroxide ions (OH-) and hydrogen gas (H2) ... 

Our theory regarding atomic size and reactivity holds true for the alkaline earth metals. As we move down a group on the periodic table, as the atomic size increases, the chemical reactivity increases. Calcium is more reactive than beryllium and magnesium. Neither the alkali metals nor the alkaline earth metals would be good candidates for jewelry making. We would not want to wear metal jewelry that might react violently to oxygen or water vapor in the air. 

The alkali metals are the most chemically active metals. Alkaline earth metals are second in reactivity. Elements in the same family have the same outermost electron configuration. Alkali metals have one outermost electron that is easily transferred to needy atoms. Alkaline earth metals have two outermost electrons to share or transfer. The transition metals are the least active. 

Indicates the pore space available for water and roots influenced by soil composition (mineral content, mineral type, and organic matter) and soil texture Affects adsorption of the chemical Affects the surface area where adsorption can take place Influences partitioning and availability of chemicals Affects ability of a soil to transmit water or air Dictates the porosity of the soil Affects the form, reactivity, solubility, availability, and toxicity of some contaminants Affects the toxicity of some substances (mainly heavy metals) with binding or antagonistic mechanisms, for example, by alkaline-earth metals and aluminum Organic matter content, type, and % carbon Influences soil sorption properties for heavy metals and... 

Reaction of Metals on Water or Dilute Acid. Electropositive metals, such as the alkali metals and alkaline earth metals, are so chemically reactive that they rapidly displace hydrogen from water or dilute acid at room temperature. Convenient laboratory methods employ sodium amalgam or calcium with water, or zinc with hydrochloric acid ... 

Rare earth elements have similar configurations in the two outermost shells. They exhibit typical metallic properties in chemical reactions. They tend to lose three electrons and exhibit a 3+ valence state. From the Periodic Table of the elements, rare earth elements are classed as less reactive than alkali metals and alkaline earth metals but more reactive than other metals. They should be stored in an inert liquid otherwise they will be oxidized and lose their metal luster. The metal reactivity increases gradually from scandium to lanthanum and decreases gradually from lanthanum to lutetium. That is to say, lanthanum is the most reactive metal of the 17 rare earth elements. Rare earth metals can react with water and release hydrogen. They react more vigorously with acids but do not react with bases. 

Fluorine is characterized by its extraordinary chemical reactivity— it is the most active of the elements. Non-metals, such as hydrogen, sulfur, iodine, and arsenic, and metalloids, such as silicon, boron, and carbon, combine spontaneously with fluorine, becoming incandescent. All metals are attacked by the gas. The alkali metals and alkaline-earth metals take fire in a stream of the gas at room temperature, whereas the more noble metals react with fluorine when warmed. Fluorine decomposes water, forming hydrogen fluoride and liberating a mixture of oxygen and ozone. 

Calcium is an alkaline earth metal. The alkaline earth metals make up Group 2 (IIA) of the periodic table, a chart that shows how the elements are related. They also include beryllium, magnesium, strontium, barium, and radium. The alkaline earth metals are more chemically active than most metals. Only the alkali metals in Group I (lA) are more reactive. 

The alkaline earth metals show a wider range of chemical properties than the alkali metals. The IIA metals are not as reactive as the lA metals, but they are much too reactive to occur free in nature. They are obtained by electrolysis of their molten chlorides. Calcium and magnesium are abundant in the earth s crust, especially as carbonates and sulfates. Beryllium, strontium, and barium are less abundant. All known radium isotopes are radioactive and are extremely rare. 

Explain how atomic radii influence the chemical reactivity of the alkaline earth metals. (Chapter 8)... 

The alkaline earth metals are somewhat less electropositive and less reactive than the alkali metals. Except for the first member of the family, beryllium, which resembles aluminum (a Group 3A metal) in some respects, the alkaline earth metals have similar chemical properties. Because their ions attain the stable electron configuration of the preceding noble gas, the oxidation number of alkaline earth metals in the combined form is almost always +2. Table 20.5 lists some common properties of these metals. Radium is not included in the table because all radium isotopes are radioactive and it is difficult and expensive to study the chemistry of this Group 2A element. 

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