٢٢٢ كيم: كيمياء المجموعات الرئيسية 222 Chem: Main Group Chemistry

1. ٢٢٢ كيم: كيمياء المجموعات الرئيسية 222 Chem: Main Group Chemistry Dr.NoufH. Alotaibi

2. كيمياء المجموعات الرئيسية Dr.NoufAlotaibi

3. 222 Chem: Main Group Chemistry Dr. Nouf Alotaibi

4. Course Description:Chemistry 222 Chem will be composed of two main components;The Chemistry of selected main group elements, followed byIntroduction to bonding in polyatomic Molecules.Part 1: Understand the structure bonding and reactivity of selected elements and their simple compounds. This will include a discussion of main group element hydrides, halides and oxides.Part 2:Introduction to bonding in polyatomic molecules, this will includea briefreview of Lewis, VSEPR andvalence bond modelsfollowed by a study of molecularshape,symmetry and Molecular orbital theory.Course Objectives:Students are expected, as a result of tutorial and associated reading, to know the concepts and theories used to describe the chemistry of the main group elements with an understanding of bonding models such as valence bond theory and molecular orbital theory for polyatomic molecules. Selected Examples illustrating the chemistry of the elements in Group 14 to 18 will be discussed. Prerequisite RequirementsThe prerequisite for this class is 107Chem. Dr. Nouf Alotaibi

5. WebsiteBLACLBOARD will be used as a main form of communication for course notes, assignments, grades and notifications. The missing of critical information due to your failure to check BLACLBOARD cannot be used as a basis for appeal. • Instructor • Dr. Nouf H. Alotaibi • Office: 5T242 • Office Hours: Sunday, Tuesday and Thursday 11-12 or by appointment. • Email: nhalotaibi@ksu.edu.sa • Email correspondence must be from your @ksu.edu.sa account. • Please include 222 Chem in the subject line • Lecture and Tutorial Information • Lectures • 3 h/week, STTh, 9-10. • Class room 021/ 01/05 •  Tutorial • 1 h/week, M 9:00- 10:00. • Class room 021/ 01/05 Dr. Nouf Alotaibi

6. Evaluation • • Tests: There will be two exams with 20 marks each and total 40 mark. • First midterm test on 29/1/1438. • Second midterm test on 5/3/1438. • • Tutorial: 20 mark, • • Final Exam: 40 mark. • Course Reference • The list here is merely suggestive and possibly representative. There are many other good books and course materials as well. • W. Henders: Main Group Chemistry, RSC Publishin, 2000. • J E Huheey, E. A. Keiter, R. L. Keiter and O. K. Medhi; Inorganic Chemistry: Principles of Structure and reactivity, Pearson Education, 2006. • P. W. Atkins, T. Overton, J. Rourke, M. Weller and F. Armstrong; Shriver & Atkins: Inorganic Chemistry, Fourth Edition, Oxford University Press, 2006. • F. A. Cotton, G. Wilkinson, C. A. Murillo and M. Bochmann; Advanced Inorganic Chemistry, Sixth Edition, Wiley, 1999. • N. N. Greenwood and E. A. Earnshaw, Chemistry of the Elements, Second Edition, Elsevier 1997. • الاسس النظرية لكيمياء المجموعات الرئيسية, مكتبة العبيكان, محمود منشي, 1994. • كيمياء المجموعات الرئيسية .محمد علي خليفة الصالح, جامعة الملك سعود. عمادة شئون المكتبات (الرياض)جامعة الملك سعود، 1990 Dr. Nouf Alotaibi

7. اولا المجموعات الرئيسية هي العناصر الواقعة في المجموعات (A)الرئيسة بالجدول الدوري للعناصر ويرمز لها بالرمز وتقع هذه المجموعات في يسار و يمين الجدول الدوري وتسمى .ايضا بالعناصر التمثيليةثانيا كيمياء هذه المجموعات يقصد به دراسة هذه العناصر من ناحية خواصها الكيميائية(تفاعلاتها - استخلاصها- مركباتها) ويدخل ضمنها الخواص الفيزيائية و تدرج خواصها • Introduction: • Main group chemistry? • Main Group elements?? • Periodic Table? • The table is a visual representation of the periodic law which states that certain properties of elements repeat periodically when arranged by atomic number. • The table arranges elements into vertical columns (Groups) and horizontal rows (Periods) to display these commonalities. Dr. Nouf Alotaibi

8. The history of the periodic table: • Chemical elements such as gold, silver and copper were known . • About 330 B.C Aristotle proposed that everything is made up of a mixture of one or more of four "roots" . • the understanding of the nature of matter. • Plato, the four elements were; • Earth, Water, Air and Fire. • Aristotle's and Plato's ideas did nothing to advance Dr. Nouf Alotaibi

9. The history of the periodic table: • Lavoisier(1789)  لافوازييه • The first modern chemical text book. • It contained a list of elements, or substances that could not be broken down further, which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc, and sulfur. • Prouts Hypothesis (1815- 1816). H2 هو المادة الاولية لتكوين جميع العناصر Dr. Nouf Alotaibi

10. The history of the periodic table: • The law of triads- dobereiner (1817). • According to Dobereiner, elements can be arranged in increasing order of their atomic mass. • He arranged all the known elements in groups of three each. • These groups are called triads. • In each triad, elements are arranged in increasing order of their atomic mass.  • The atomic mass of the middle element is equal to the average atomic mass of both the terminal elements. These triads are also termed as Dobereiner triads. Dr. Nouf Alotaibi

11. The history of the periodic table: • Octaves Law of Newlands (1864). • Elements arranged in order of their relative atomic masses. • any given element will exhibit analogous behaviour to the eighth element following it in the table. • Newland assumed only 56 elements existed so far. Later new elements were discovered which did not fit into octaves table.  • Newland adjusted few elements in a same slot though their properties were quite different. E.g. Cobalt and nickel are in the same slot and these are placed in the same column as fluorine, chlorine and bromine which have very different properties than these elements. Dr. Nouf Alotaibi

12. The history of the periodic table: • (1869-1870) ? Who Is The Father of the Periodic Table ? • The German Lothar Meyer or the Russian Dmitri Mendeleev. • Both chemists produced similar results at the same time working independently of one another. • Mendeleev: (1869) • 63 known elements. • Element's symbol, atomic weight and its characteristic chemical and physical properties. • Mendeleev arranged the elements in a table ordered by atomic weight(molar mass). • Mendeleev's table became available (1869). • Nobel Prize (1906). Meyer: (1864-1870) • Half of the known elements (28). • demonstrated periodic valence changes as a function of atomic weight. • Meyer constructed an extended table which he gave to a colleague for evaluation (1868). • Meyer's table appeared (1870). Dr. Nouf Alotaibi

13. Mendeleev: (1869) • The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties. • Elements which are similar as regards to their chemical properties have atomic weights which are either of nearly the same value (e.g., Pt, Ir, Os) or which increase regularly (e.g., K, Rb, Cs). • The arrangement of the elements, or of groups of elements in the order of their atomic weights, corresponds to their so-called valencies, as well as, to some extent, to their distinctive chemical properties; as is apparent among other series in that of Li, Be, Ba, C, N, O, and Sn. • The elements which are the most widely diffused have small atomic weights. • The magnitude of the atomic weight determines the character of the element. • We must expect the discovery of many yet unknown elements–for example, elements analogous to aluminium and silicon–whose atomic weight would be between 65 and 75. • The atomic weight of an element may sometimes be amended by a knowledge of those of its contiguous elements. However Moseley later explained the position of these elements without revising the atomic weight values . • Certain characteristic properties of elements can be foretold from their atomic weights. Dr. Nouf Alotaibi

14. Elements or properties of elements depend periodically on their atomic weights. • Mendeleev (1869) Dr. Nouf Alotaibi

15. This version of Mendeleev's periodic table from 1891. It is lacking the noble gases. https://upload.wikimedia.org/wikipedia/commons/5/5f/Mendeleev_Table_5th_II.jpg Dr. Nouf Alotaibi

16. Scientific benefits of Mendeleev's table: • Mendeleev predicted the discovery of other elements and left space for these new elements, namely eka-silicon (germanium), eka-aluminium (gallium), and eka-boron (scandium). Thus, there was no disturbance in the periodic table. • He pointed out that some of the then current atomic weights were incorrect. • He provided for variance from atomic weight order. • Shortcomings of Mendeleev's table: • His table did not include any of the noble gases, which were discovered later. These were added by Sir William Ramsay as Group 0, without any disturbance to the basic concept of the periodic table. • There was no place for the isotopes of the various elements, which were discovered later. Dr. Nouf Alotaibi

17. Discovery of the Noble Gases: • In 1895 Lord Rayleighريليه • New gaseous element named argon proved to be chemically inert. • This element did not fit any of the known periodic groups. • In 1898, William Ramsey • Argon be placed into the periodic table between chlorine and potassium in a family with helium. • Argon's atomic weight was greater than that of potassium?!!. • This group was termed the "zero" group (zero valency of the elements). • Ramsey accurately predicted the future discovery and properties neon. Dr. Nouf Alotaibi

18. Atomic Structure and the Periodic Table: • Ernest Rutherford(1911) • Studiedthe scattering of alpha particles by heavy atom nuclei, determinate the nuclear charge. شحنة النواة • Demonstrated the nuclear charge on a nucleus was proportional to the atomic weight of the element. • A. van den Broek(1911) • The atomic weight of an element was approximately equal to the charge on an atom. • This charge ( later called the atomic number)could be used to number the elements within the periodic table. • Henry Moseley (1913) موزلي • Measured the wavelengths of the x-ray spectral lines of a number of elements which showed that the ordering of the wavelengths of the x-ray emissions of the elements coincided with the ordering of the elements by atomic number. • With the discovery of isotopes of the elements, it became clear that atomic weight was not the significant player in the periodic law as Mendeleev, Meyers and others had proposed, but rather, the properties of the elements varied periodically with atomic number. Dr. Nouf Alotaibi

19. Atomic number vs. Atomic weight: The atomic number of an atom is simply the number of protons in its nucleus.  The atomic weight is given in most cases by the mass number of the atom, equal to the total number of protons and neutrons combined. Dr. Nouf Alotaibi

20. The Modern Periodic Table: • The last major changes to the periodic table resulted from Glenn Seaborg's work in the middle of the 20th Century. • Discovered plutonium (Pu) in 1940; • Discovered all the transuranic (ما بعد اليورانيوم) elements from 94 to 102; • Reconfigured the periodic table by placing the actinide series below the lanthanide series. • Nobel Prize in chemistry (1951). • Element 106 has been named seaborgium (Sg). Dr. Nouf Alotaibi

21. 2011: added elements 114 and 116. • International Union of Pure and Applied Chemistry (IUPAC) on 13 December 2015 announced a researchers from Russia and US reached a sufficient evidence of the discovery of new elements, which are 113, 115, 117, 118. • 8 June 2016: IUPAC is naming the four new additions to the table: • nihonium, moscovium, tennessine, and oganesson. نيهونيوم موسكوفيومتينيسيناوغانيسون Dr. Nouf Alotaibi

22. How Many Elements Can Be Found in the periodic table? 118 elements How Many Elements Can Be Found Naturally? 98 elements Elements 93-98 (neptunium, plutonium, americium, curium, berkelium, and californium) were all first artificially synthesized and isolated in the Berkeley Radiation Laboratory of the University of California. Dr. Nouf Alotaibi

23. The Modern Periodic Table: • Periodic table contains; 7 horizontal rows (periodes), and 18 vertical columns (groups). • Four sections: the Right, the Left, and the middle, and the end of the table. • Section left: the main group elements (A): two groups (A1, A2) and called (the alkali metals). • Section right: the rest of the group (A); (A3 to A7), • defined as non-metals, and semi-metals, and the rest of other metals, and Nobel gases, or inert and halogens. • Middle section: group (B), includes 30 component, called the transitional elements. • The final section consists of two series of elements : • First series: called lanthanides, includes 14 elements, and begin the element cerium. • Second Series: called actinides, includes 14 element, and begin the element thorium Dr. Nouf Alotaibi

24. Dr. Nouf Alotaibi

25. p-block s-block d-block f-block Dr. Nouf Alotaibi

26. The Modern Periodic Table- Classification of elements: Videos https://www.youtube.com/watch?v=t_f8bB1kf6M&feature=youtu.be https://youtu.be/t_f8bB1kf6M Transcript https://www.khanacademy.org/science/chemistry/periodic-table/copy-of-periodic-table-of-elements/v/periodic-table-introduction Dr. Nouf Alotaibi

27. Periodic Trends • Arises from the Periodic patterns in ELECTRON CONFIGURATIONS. • Elements in the same GROUP have the same number of VALENCE electrons • VALENCE electrons = electrons in the outermost orbital • Chemical and physical properties of element depend on the Atomic Electron Configurations ( valence electrons) • Observed trends in • Sizes of atoms and ions. • Ionization energy. • Electron affinity. Dr. Nouf Alotaibi

28. Sizes of Atoms • The bonding atomic radius is defined as one-half of the distance between covalently bonded nuclei. Dr. Nouf Alotaibi

29. Sizes of Atoms Bonding atomic radius tends to… …decrease from left to right across a row due to increasing Zeff. …increase from top to bottom of a column due to increasing value of n increasing Eff increasing n Dr. Nouf Alotaibi

30. For the same shell value (n) the penetrating power of an electron follows this trend in subshells: s>p>d>f Dr. Nouf Alotaibi

31. As we move ACROSS the periodic table, the nuclear charge increases while  the number of energy levels occupied by electrons remains the same. • The number of core electrons remains constant. Dr. Nouf Alotaibi

32. Which of the following ATOMS is largest N , O , F? S or O? Na or Cl? Na or K? ----- Same period, N ----- Same group, S ----- Same period, Na ----- Same group, K Dr. Nouf Alotaibi

33. Sizes of Ions Ionic size depends upon: • Nuclear charge. • Number of electrons. • Orbitals in which electrons reside. • CATIONS lose electrons and are SMALLER THAN THE PARENT ION. • ANIONS add electrons and are LARGER THAN THE PARENT ION. Dr. Nouf Alotaibi

34. Sizes of Ions • Cations are smaller than their parent atoms. • The outermost electron is removed and repulsions are reduced. • Zeff increase Dr. Nouf Alotaibi

35. Sizes of Ions • Anions are larger than their parent atoms. • Electrons are added and repulsions are increased. • Zeff decrease Dr. Nouf Alotaibi

36. Sizes of Ions • Ions increase in size as you go down a column. • Due to increasing value of n. Dr. Nouf Alotaibi

37. Sizes of Ions • In an isoelectronic series, ions have the same number of electrons. • Ionic size decreases with an increasing nuclear charge. Dr. Nouf Alotaibi

38. Dr. Nouf Alotaibi

39. ISOelectronic series A group of ions all containing the same number of electrons How many electrons do O2- ; F- ; Na+ ; Mg2+ and Al3+ have ? 10 -- Increasing nuclear charge O2- > F- > Na+ > Mg2+ > Al3+ --- Decreasing ionic radius Dr. Nouf Alotaibi

40. K+ and Ca2+ (18) Ca2+ andSc3+ (18) S2- and Ar (18) Fe2+ andCo3+ (24) Dr. Nouf Alotaibi

41. Which of the following is largest ? • Na or K ? • Na or Mg ? • S2– or O2– ? • S2–, S, or O2– ? • K+, Cl–, Ca2+ , or S2– ? • O2– , F- , Na+ , Mg 2+ , or Al 3+ Dr. Nouf Alotaibi

42. Arrange the ions K+, Cl–, Ca2+ and S2– in order of DECREASING size. • These form an isoelectronic series of ions • Size decreases as the nuclear charge of the ion increases. • The atomic numbers of the ions are S (16), Cl (17), K (19), and Ca (20) • K+, Cl–, Ca2+ and S2– all have 18 • -- Increasing nuclear charge • --- Decreasing ionic radius • S2– > Cl–> K+ > Ca2+ • Arrange O 2- , F - , Na + , Mg 2+ , Al 3+ according to size • As nuclear charge increases in an isoelectronic series the ions become smaller • all have 10 • O 2-> F - Na + Mg 2+  Al 3+ Dr. Nouf Alotaibi

43. Ionization Energy • Amount of energy required to remove an electron from the ground state of a gaseous atom or ion. • First ionization energy is that energy required to remove first electron. • Second ionization energy is that energy required to remove second electron, etc. El ------- El+ + e- Example: Na ------- Na+ + e- Dr. Nouf Alotaibi

44. Ionization Energy • It requires more energy to remove each successive electron. • When all valence electrons have been removed, the ionization energy takes a quantum leap. Dr. Nouf Alotaibi

45. Periodic Trends in Ionization Energies Ionization energy decreases going down a group Ionization energy generally increases across a period. Dr. Nouf Alotaibi

46. Trends in First Ionization Energies • going down a column, less energy to remove the first electron. For atoms in the same group, • Zeff is the same, but • the valence electrons are farther from the nucleus. Dr. Nouf Alotaibi

47. Trends in First Ionization Energies Generally, it gets harder to remove an electron going across. • As you go from left to to right, Zeff increases. Dr. Nouf Alotaibi

48. Trends in First Ionization Energies n-=2, 4Be:1s22s2 5B:1s22s22p1 7N:1s22s22p3 8O:1s22s22p4 On a smaller scale, there are two jags in each line. Why? Dr. Nouf Alotaibi

49. Dr. Nouf Alotaibi

50. Dr. Nouf Alotaibi