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4 Referring to the periodic table of the elements (ssss1), which of the reactive (non‐Noble) elements is the most metallic (electropositive) and which of these is the most nonmetallic (electronegative). Use their electron configurations and position on the periodic table to explain why.

5 Explain the differences between ionic, covalent, metallic, and transitional (hybrid) bonds and the properties that commonly characterize materials that possess that type of bond.

6 Using the periodic table of the elements (ssss1), calculate the electronegativity difference and then predict the bond type and properties for each of the following minerals:Native platinum (Pt)Periclase (MgO)Sylvite (KCl)Pyrite (FeS2)Sphalerite (ZnS).

7 Explain the concepts of radius ratio and electrostatic valency and use them to explain why silica tetrahedra tend to link by sharing oxygen ions. Then describe and explain the basic differences between nesosilicate, sorosilicate, cyclosilicate, nesosilicate, phyllosilicate and tectosilicate structures.