Atoms and nuclei neutron proton a=Z+N Ato Mass CR 4 6 electron atom size≈10 Atomic‖ Neutron nucleus NumberNumber sie≈5x0-15m nucleus ['nju: klias Atomic Number:原子序数 Neutron number:中子数 Nuclei. pl Mass Number:质量数
Atoms and Nuclei Atomic Number:原子序数 Neutron Number:中子数 Nuclei, pl. Mass Number:质量数
Isotopes Atoms having the same atomic number Z but different numbers of neutrons w are called isotopes of the element identified by Z and all elements have a number of Isotopes O.170.18O Specially, Hydrogen H, deuterium H, and tritium H
Isotopes • Atoms having the same atomic number Z, but different numbers of neutrons N are called isotopes of the element identified by Z, and all elements have a number of isotopes. • 16O, 17O, 18O • Specially, Hydrogen 1H, deuterium 2H, and tritium 3H
The Periodic table of the elements Main groups Other groups Main groups lⅢⅣvvvW IlⅢⅣVv Jvm) He Li Be BCNOFNe ca sc ti v cr Mn Fe co Ni cu zn Ga Ge As se IK Rb Sr Zr Nb Mo Tc Ru Rh Pd Ag cd In Sn SbTe cs Ba Hf ta w Re os Ir Pt au Hg ti Pb Bi Po At Rn Fr Ra Ku Ha Sq Ns Hs Mt UunU Lanthanoids La ce Pr Nd Pm sm Eu Gd Tb Dy Ho Er Tm Yb Lu ids Ac Th Pa u Np Pu Am Cm Bk cf Es Fm Md N Background color Metal Font color= Solid states Background color Metalloid Font color= Liquid Background color= Nonmetal Font color
Words must be remembered Atom,原子 Nucleus,原子核 Nuclei, nucleus的复数形式 Nucleon,核子 Electron,电子 Proton,质子 Neutron,中子 Orbita,轨道的
Words must be remembered • Atom, 原子 • Nucleus, 原子核 • Nuclei, nucleus 的复数形式 • Nucleon,核子 • Electron, 电子 • Proton, 质子 • Neutron，中子 • Orbital, 轨道的
The nucleus Let's take a look at the nucleus, where the protons and neutrons reside Breaking these apart can cause a large release of energy Neutron(n) Proton(p) Protons Repel Attract
The Nucleus Let’s take a look at the nucleus, where the protons and neutrons reside. Breaking these apart can cause a large release of energy. Protons
Words must be remembered Element,元素 Isotope,同位素 Hydrogen,氢 Uranium,铀 Radioactive,ad,放射 性的 Fissile,ad,易裂变的 Emission,n.发射 Decay,v,n,衰变 Radiation,n,放射性, 放射,射线
Words must be remembered • Element, 元素 • Isotope，同位素 • Hydrogen, 氢 • Uranium, 铀 • Radioactive, adj.,放射 性的 • Fissile, adj.,易裂变的 • Emission, n.发射 • Decay, v., n., 衰变 • Radiation， n., 放射性， 放射，射线
Mass Defect质量亏损 The principle of the equivalence of mass and energy E=mc where c, the speed of light, is 2.998X 108 m/s
Mass Defect 质量亏损 • The principle of the equivalence of mass and energy: where c, the speed of light, is 2.998×108 m/s 2 E mc
What is Radioactivity? Elements that are radioactive are UNSTABLE because they have too many nucleons or too much energy. In an attempt to become STABLE, they give up particles or energy and this IS RADIOACTIVITY From Latin radioto(to radiate)
What is Radioactivity? Elements that are RADIOACTIVE are UNSTABLE because they have too many nucleons or too much energy. In an attempt to become STABLE, they give up particles or energy and this is……. RADIOACTIVITY From Latin radioto (to radiate)
Radioactivity Unstable Stable Stable RADIOACTIVE 12 14 C C
Radioactivity C 12 6 Stable C 13 6 Stable C 14 6 Unstable RADIOACTIVE
Radioactivity Unstable RADIOACTIVE The nucleus of this atom is very heavy because it contains two extra NEUTRONs In order to become stable it needs to get rid of some excess weight 14
Radioactivity C 14 6 Unstable RADIOACTIVE The nucleus of this atom is very heavy because it contains two extra NEUTRONS In order to become stable it needs to get rid of some excess weight
