麻省理工公开课：固态化学PPT课件第2课时.pdf

Welcome to 3.091 Lecture 2 September 11, 2009 The Periodic Table Public domain image from Wikimedia. John Dalton 1803 Public domain image from Wikimedia. Dalton’s Model of the Atom (1803) 1. Matter is composed of atoms that are indivisible and indestructible. 2. All atoms of an element are identical. 3. Atoms of different elements have different weights and different chemical properties. 4. Atoms of different elements combine in simple whole number ratios to form compounds. 5. Atoms cannot be created or destroyed. When a compound is decomposed, the atoms are recovered unchanged. 1869 H He Li Be B C N O Na Mg Al Si P S Cl K Ca Ti V Cr Mn Fe Co Ni Cu Zn As Se Br Rb Sr Y Zr Nb Mo Ru Rh Pd Ag Cd In Sn Sb Te I Cs Ba Ta W Os Ir Pt Au Hg Tl Pb Bi La Ce Tb Er Th U Image by MIT OpenCourseWare. 1869 Image by MIT OpenCourseWare. principles of modern chemistry: * recognize patterns * develop a quantitative model that - explains our observations - makes predictions that can be tested by experiment Comparison of eka-silicon with germanium eka-silicon germanium 72 g/mol 72.59 g/mol 5.5 g/cm3 5.36 g/cm3 “high” m.p. m.p. =