1. Pre knowledge Atomic structure

2. OBJECTIVES: Each students should be able to recall: 1- the structure of the atom. 2- charge and mass of particles in the atom. 3- mass number and atomic “proton” number. 4- symbols of some elements.

3. Previous Knowledge atom heavy protons electronsnucleus An __________ is the smallest possible particle of an element that can exist. The atom consists of a tiny, massive central ____________ surrounded by moving ________. atom nucleus electrons

4. Previous Knowledge atom protons neutron positivelynegatively The Nucleus contains the __________ and neutrons. Protons are ______________ charged particles. protons positively

5. Previous Knowledge heavy neutron elements The nucleus is the ______________ part of the atom (protons and neutrons have much greater mass than electrons). Atoms of different _______________ contain different number of protons. heavy elements

6. Previous Knowledge positivelyenergy level next elementscharge Each _______________ in an atom can only contain a set number of electrons. Once an energy level is full any extra electrons go into the ________ energy level. Atoms have no overall _______________, therefore the number of protons is the same as the number of electrons. energy level charge next

7. Previous Knowledge 1113 protons neutron electrons ions The atomic number is the number of ________ in the nucleus, or the number of ____________ in the energy levels. The number of protons in sodium atom “ 11 Na 23 “ is _______________, and that equals the number of ____________ in neutral atom. protons electrons 11 electrons

8. Previous Knowledge positive ionic Negative covalent When an atom loses electrons it becomes a ________ ion, but when an atom gains electrons it becomes a ____________ ion. Chemical bonding might be ________, or ____________. positive negative ionic covalent

9. In the periodic table, elements are represented as follow. z X A e.g. 11 Na 23 This tells us: The atomic number of sodium = 11 The mass number of sodium = 23

10. Look at the periodic table of elements and write down the atomic number A and the mass number Z for the following elements. magnesium Mg potassium K oxygen O fluorine F neon Ne A Z Periodic table

11. ParticleRelative ChargeRelative Mass Proton+11 Neutron01 Electron–10 (1/1840) Use the following information to answer the questions. The charge of proton is positive while the charge of electron is ____________. The particle with no charge is ________________. The mass of ___________ is negligible. The mass of __________ and ___________ are equal. Negative the neutron electron proton neutron

12. Names and symbols of common elements

13. Periodic table of elements Back