Question

why berillyium and magnesium are polymers
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Answer 1

Answer:

They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure.

Answer 2

Explanation:

Beryllium can be thought of as being even more covalent than magnesium. The small size (ca. 0.3 Å) results in a very high charge density of Be2+. In addition, the ionization energy for beryllium is a large positive value (1st ionization energy = 899.5 kJ/mol, 2nd ionization energy = 14,848.7 kJ/mol). Both of these factors means that the free ion does not exist. Instead, beryllium forms covalent compounds in a similar manner to its diagonal analog aluminum. Both beryllium and aluminum form covalent compounds or strongly solvated cations, and both form polymeric hydrides, chlorides, and alkyls.

The ionic radius for the +2 cation of magnesium is fairly small (0.65 Å). As a consequence the charge density (z/r) is high, which results in a high polarizing power of the Mg2+ ion. Thus, magnesium tends to form polar covalent bonds rather than ionic complexes. As with lithium there is a wide range of organometallic derivatives of magnesium, especially the Grignards (RMgX, where X = Cl, Br

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