Lesson 5


LESSON 5.  Symmetry of Elements (Lab)


Objective:  Students learn that elements on the microscopic level have symmetry.



           Periodic Table of Elements (placemats)


Teacher Notes:


This unit looks at symmetry at the element level.  It is a way to introduce a new concept to students while reviewing the different elements.   Emphasize with students that symmetry can be found at all levels, from large pieces to subatomic.  Use the example provided in the reader of the different properties that can found on the Periodic Table of the Placemats.  In subsequent readings and lab, students will learn more about the Periodic Table.  

Go over the codes on the placemat and then have the students list the elements. You can either have them write out the element or just use the symbol. 



1.  three, solid, liquid, gas;  synthetic elements do not list a state of matter

2.  Cubic, face centered:  Ne, Ar, Kr, Xe, Rn, Al, Si, Pb, Ge, Cu, Ag, Au, Pt, Pd, Ni, Rh, Ir, Ac, Sr, Ca, Ce, Yb, Th
Cubic, body centered:  Fe, Mn, Cr, Mo, W, Ta, Nb, V, Ra, Ba, Li, Na, K, Rb, Cs, Fr, Eu
Cubic:  F, O, Pa, U, Np
Hexagonal, He, Te, Se, N, C, Ti, Zn, Cd, Co, Os, Ru, Re, Hf, Zr, Ti, Sc, Y, La, Mg, Be, H, Pr, Nd, Pm, Gd, Tb, Dy, Ho, Er, Tm, Lu
Rhombohedra:  Cl, B, As, Sb, Bi, Hg, Sm
Tetragonal, Sn, In
Orthorhomic, I, Br, S, Ga
Monoclinic: Po, P, Pu

3.  they are synthetically prepared

4.  up to students “pattern”

5.  Nobel gases except for He are cubic face centered; Alkali metals are cubic, body centered



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