![]() (a) Higher melting points (b) Higher boiling points Due to the presence of stronger metallic bonds, alkaline earth metals have Consequently, stronger metallic bonds are formed which result in the close packing of the atoms. Moreover, sizes of alkaline earth metal ions are smaller than those of alkali metal ions. The alkali metal two electrons are involved in the metallic bonding. (v) Nature of metallic bonding in alkaline earth metals ![]() Lattice energies decreases as atomic number increases Thus, unlike alkali metals, the alkaline earth metals exhibit +2 oxidation state in their compounds. The alkaline earth metal have two electrons in their valence shell and by losing these electrons, these atoms acquire the stable noble gas configuration. The general reactivity trend is Ba > Sr > Ca > Mg > Be. Because their (IE)1 is larger than that of their alkali metal neighbours, the group IIA metals trend to the some what less reactive than alkali metals. It is because of increase in atomic size due to addition of new shells and increase in the magnitude of screening effect of the electrons in inner shells. However with in the group, the ionization energy decreases as the atomic number increases. The alkaline earth metal owing to their large size of atoms have fairly low values of ionization energies as compared to the p – block elements. The atomic radii as well as ionic radii of the members of the family are smaller than the corresponding members of alkali metals. The general electronic configuration of alkaline earth metals is ns2.Ĭa – 1s 22s 22p 63s 23p 64s 2 Sr – 5s 2 Sr – Celestite (SrSO 4), Strontianite (SrCO 3) ![]() Mg – Magnesite MgCO 3, Dolomite CaMg(CO 3) 2, Epsomite MgSO 4.&H 2OĬa – Limestone (CaCO 3), fluoropatite, Gypsum (CaSO 4.2H 2O), Anhydrite (CaSO 4) Like alkali metals, alkaline earth metals are also highly reactive and hence do not occur in the free state but are likely distributed in nature in the combined state as silicates, carbonates, sulphates and phosphates.īe – Beryl (Be 3Al 2Si 6O 18) & Phenacite (Be 2SiO 4) The name alkaline earth metals was given to magnesium, calcium, barium & strontium since their oxides were alkaline in nature and these oxide remained unaffected by heat or fire and existed in earth. They are Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba) and Radium (Ra). The group 2 of the periodic table consists of six metallic elements.
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