Atomic structure原子结构

1、葡萄干面包模型葡萄干面包模型 太阳系模型太阳系模型 电子壳层模型电子壳层模型 电子云模型电子云模型Dalton Thomson Rutherford Bohr protons neutronselectric neutrality )neutrons (negative negativeelectric neutrality nutrlti XAZMass numberAtomic numberAtomic number，Z=number of protonsMass number，A=number of protons + number of neutrons The number of P

2、rotons = Number of ElectronsThe number of neutrons=A-ZC126C146U23592U23892C136U23492 )(%)(%AtMassBBAtMassAAAveAtMassThe element copper is found to contain the naturally occurring isotopes and . The relative abundances are 69.1% and 30.9% respectively. Calculate the average atomic mass of copper.Cu63

3、29Cu6529AveAtMass)63%1 .69()65%9 .30(=amu6.63AveAtMassAtomic mass unitANSWER: 39.95 amuBe94Al2713Ag10847Mn5525I13153Be94Radioactivity is the spontaneous emission of radiation from radioisotope. X-rays and g g-rays are high-energy light which can kill cancer cells.a a-particles are a stream of helium

4、 nuclei, He2+.b b-particles are a stream of high speed electrons that originate in the nucleus. Arranged in the shell of lowest energy first Each shell configuration can be at most 2 n2 electrons layers for K, most can only hold two electrons. Other layers as the outermost layer can only accommodate

5、 8 electrons. outer electronic time is no more than 18 electrons K L MN O P2 8 183250 2n21 2 3 4 5 6 Configuration of extra-nuclear electron 1s11s22s11s22s22p63s11s22s22p63s23p64s11s22s22p63s23p63d104s24p65s11s22s22p63s23p63d104s24p64d105s2 5p66s11s22s22p63s23p63d104s24p64d104f145s25p65d106s26p67s1H1Li3Na11K19Rb37Cs55Fr87Increasing energy1s2s3s4s5s6s7s2p3p4p5p6p3d4d5d7p6d4f5f6fOrbitals available to a Hydrogen atomIncreasing energy1s2s3s4s5s6s7s2p3p4p5p6p3d4d5d7p6d4f5fWith more electrons, repulsion changes the energy of the orbitals.More examples Ge = 1s2