Atoms, molecules and compounds by waqar

General Chemistry by Dr.Waqar

1. A Motivational Lesson by Dr. Waqar Ahmad Pharm-D (Gold Medalist) M.Phil Pharmacy (QAU Islamabad)

2. Matter are made up of tiny & discrete particles Size of particles are very minute ~~ 1x 10 -7 cm 3. Consist of atoms , molecules ions N e x t

3. Let’s see the particles in bromine liquid Particle theory

4. The smallest particle of an element and not breakable anymore. Examples: Atom of hydrogen atom of magnesium atom of oxygen atom of chlorine H Mg C l O Particle theory

5. A group of two or more atoms, which might consist of: one type of element (Element) Or different types of element (Compound)

6. Examples of element molecules: Molecule of hydrogen gas Molecule of oxygen gas Molecule of chlorine gas O O Cl Cl H H

7. Ions are atoms which have charge Positively-charged ion / cation (loss e - ) Negatively charged ion / anion (gain e-) + -

8. Hydrogen atom Hydrogen ion Magnesium atom O x y g e n atom Chlorine atom Chlorine ion H + H Lose electron Lose electron M g Magnesium ion Mg 2+ Oxide ion O 2 - Gain electron O Cl - Gain electron Cl Particle theory Symbol of element Examples of ions:

9. 2.2 ATOMIC STRUCTURE

10. The Historical Development Of Atomic Models John Dalton – imagine atom as a indivisible tiny ball J.J. Thomson – discovered electrons Ernest Rutherford – discovered proton, mass of atom concentrated in nucleus Neils Bohr – proposed the electrons move in shells around the nucleus James Chadwick – proved the existence of neutrons

11. Subatomic Particle In An Atom

12. Subatomic Particle In An Atom Proton Neutron E lec t r o n

13. Subatomic Particle In An Atom Proton Electron Neutron N ucle u s of atom E lec t r o n shells

14. Subatomic Particle In An Atom

15. Subatomic Particle In An Atom

16. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol Electric Charge Relative Mass Location

17. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p Electric Charge Relative Mass Location

18. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n Electric Charge Relative Mass Location

19. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge Relative Mass Location

20. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 Relative Mass Location

21. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 Relative Mass Location

22. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass Location

23. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 Location

24. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 1 Location

25. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 1 1/1240 ≈ Location

26. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 1 1/1240 ≈ Location in the n u c l e us atom

27. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 1 1/1240 ≈ Location in the n u c l e us atom in the nu c l e us atom

28. Subatomic Particle In An Atom PROPERTIES PROTON NEUTRON ELECTRON Symbol p n e - Electric Charge +1 -1 Relative Mass 1 1 1/1240 ≈ Location in the n u c l e us atom in the nu c l e us atom Electron shells which around the nucleus atom

29. 20 40 Ca Nucleon number Proton number Symbol of Element ( 1. refer ions) -When an atom is neutral , its number of proton = e - number of protons = 20 so number of elecrons = 20 2. e l ec tron c o n f ig u rat i o n = 2 . 8 . 8 . 2 valence electron = 2 Symbol of element 3 . N ext

30. Electron Configuration Also known as electron arrangement How electrons fill into the shells?

31. Helium He Proton number 2 2 H y d r o g en H Proton number 1 1 Lithium Proton number Li 3 2 . 1 Beryllium Proton number B e 4 2 . 2

32. B o r on B proton number 5 2 . 3 Carbon Proton nu mber C 6 2 . 4 Nitrogen Proton number N 7 2 . 5 Oxygen Proton number O 8 2 . 6

33. Fluorine Proton number F 9 2 . 7 N e on Proton number N e 10 2 . 8 Sodium Proton number N a 11 2 . 8 . 1 Magnesium Proton number Mg 1 2 2 . 8 . 2

34. Aluminium Proton number Al 13 2 . 8 . 3 Si l i c on Proton number Si 14 2 . 8 . 4 Phosphorus Proton number P 15 2 . 8 . 5 Sulphur Proton number S 16 2 . 8 . 6

35. Chlorine Proton number Cl 17 2 . 8 . 7 A r g o n A r Proton number 1 8 2 . 8 . 8 Potassium K Proton number 19 2 . 8 . 8 . 1 Calcium Ca Proton number 20 2 . 8 . 8 . 2

36. Conclusion: 1st Shell: max 2 e- 2nd Shell: max 8 e- 3rd Shell: max 8 e-

37. ARRANGEMENT OF SHELLS IN AN ATOM NU C LE U S 2 ELECTRONS 8 ELECTRONS 8 ELECTRONS 18 ELECTRONS 1 2 3 4

38. Electron arrangement in the carbon atom C 1 2 6 proton number = 6 number of protons = 6 number of electrons = 6 2 . 4 = electron nucleus Number of valence electrons = 4

39. 2 3 1 1 N a 2 . 8 . 1 number of protons = 11 proton number = 11 number of electrons = 11 = e l e c tr o n Nucleus Number of valence electrons = 1 Symbol of element

40. T r y t o d r a w o u t t h e electron a rr a n g e m e n t i n shells

41. Draw & state the electron arrangement of the elements below X 1 5 7 Y 2 4 1 2 Z 3 9 1 9

42. L e t u s l e a r n s o m e chemical words !!

43. Proton number (p) – number of protons in the nucleus of atom Nucleon number (p+n)– total number of protons and neutrons in the nucleus of atom Valence electron – the electrons in the outermost shell Electron configuration – arrangement of electron

44. Elements Proton N u m be r N u c l e o n Nu m b e r Number of N e u tro ns A 3 7 B 6 12 C 19 10 D 16 16 E 17 18 F 40 20 Q 1 Fill in the blanks

45. Elements Proton N u m be r N u c l e o n Nu m b e r Number of N e u tro ns A 3 7 4 B 6 12 6 C 9 19 10 D 16 32 16 E 17 35 18 F 20 40 20 Q 1 A n s we rs

46. Elements Number of N eu tr on Nucleon N u m b e r Number of e l e c t r o n s Electron C o n f i g u r a tio n A 5 9 B 8 2.6 C 19 2.7 D 14 2.8.3 E 32 16 F 20 40 Q 2 Fill in the blanks

47. Elements Number of N eu tr on Nucleon N u m b e r Number of e l e c t r o n s Electron C o n f i g u r a tio n A 5 9 4 2.2 B 8 16 8 2.6 C 10 19 9 2.7 D 14 27 13 2.8.3 E 16 32 16 2.8.6 F 20 40 20 2.8.8.2 Q 2 A n s w e rs

48. 2.3 ISOTOPES

49. Isotopes is just like twins , same genetic but different of DNA atoms of the same element with same number of protons but different number of neutrons What is isotopes?

50. Examples of Isotopes Take a look at Wikipedia isotopes table Hydrogen : Graphite : O x yge n : 1 H 1 3 H 1 2 H 1 12 C 6 14 C 6 13 C 6 16 O 8 18 O 8 17 O 8

51. Isotopes of Hydrogen Hydrogen : 1 1 H 2 1 H 3 1 H

52. Conclusion: Number of valence electron are same The chemical properties also same The physical properties might be same, might be different

53. Elements Proton Number Nucleon Number P 3 7 Q 9 19 R 16 32 S 15 31 T 16 33 U 18 40 Q3. Answer the structure questions

54. a ) What means proton number? A: The numbers of proton in the nucleus of an atom What means nucleon number? A: The numbers of proton & neutron in the nucleus of an atom Write the electron arrangement for element Q. A: 2.7 How many valence electrons that element Q has? A: 7 How many electron shells that element Q has? A: two

55. f) Which pair of elements are isotopes? Explain. A: R & T. Because they have same proton number but different nucleon number g) Is R&T have same chemical properties? Why? A: Yes. Because U they have same valence electron How many protons, neutrons, and electrons are t h e r e in a t o m 40 S ? 18 A: 15 protons, 16 neutrons and 15 electrons i) Write the symbol to represent atom U. A : 4 1 8 U