Atomic Structure
The Structure of the AtomThe AtomAtoms are basic building blocks ofmatter, and cannot be chemicallysubdivided by ordinary ...
in 1808 John Dalton (an Englishscientist) states a theory about thenature of the elements known asDalton’s atomic theory ,...
Elements are made of a tiny particlecalled an atom. All atoms of a given element areidentical.The atoms of a given element...
Atoms of one element can combinewith  atoms of other elements to form  compounds.  In chemical reactions atoms are neither...
Later on Thomson &                Rutherformed worked on the                structure of the atom & they                di...
Atoms are composed of three type of particles:  Protons  Neutrons  Electron
The mass & charge of the electron, proton      & neutron are given below:       particle   Relative   Relative            ...
Modern atomic theory:           In 1911 Niels Bohr construct a           model of the hydrogen atom with           quantiz...
Bohr’s atomic orbital:•    Is a specific path on which the    electrons travel about the nucleus.                         ...
Although Bohrs model opened the    way for the later theories it isimportant to realize that electrons donot move around t...
Later on Schrodinger found that it     is not precisely to describe theelectrons path , he could only   predictthe probabi...
•     In its ground state the hydrogenelectron has a probability map       The probability map, or orbital that     descri...
Shrodinger showed that the orbitals   of electrons are regions of electron   density with the location and routsof        ...
Isotopes:Atoms with the same number ofprotons but different number ofneutrons. In nature elements areusually found as a mi...
Hydrogen 1 (hydrogen)       Hydrogen 2 (deuterium)       Hydrogen 3 (tritium) 1 proton, 0 neutrons         1 proton, 1 neu...
ExampleThree isotopes of elemental carbonare C612 , C613, C614 . Determine thenumber of each of the three types subatomic ...
Atomic number:The number of protons in the nucleus.Mass number:The sum of the number of neutrons &number of protons in a g...
Ions: •       Under certain circumstances it is        possible to remove electrons from a       neutral atom leaving a po...
Atomic OrbitalQuantum numbers:     The various orbitals available to an atom are   described    by four quantum numbers, w...
The principal quantum number (n)describes the:        Shells:(an electron shell is collection of     orbitals)      Size ...
The subsidiary quantum number (l)describes the:             Subshells : are groups of orbitals with in         an electron...
The magnetic quantum number (m)describes:    Orientation of the orbitals in space.    Named after the directions they po...
The spin quantum number (s). describes:        spin of an electron on its own axis        May have the values +½ or -½.   ...
The Quantum Numbersname                 symbol valuesPrincipal QuantumNumber               n       any integer from 1 to i...
orbital                     Max no. ofL-value             No. of orbitals           type                       electrons  ...
Using symbols, the valid quantumstates can be listed in the followingmanner:             1s                    2s 2p      ...
Atomic Orbitals The S Orbital    The simplest orbital in the atom is the 1s orbital.    The 1s orbital is simply a sphere ...
1s Shell
The P Orbitals  Starting from the 2nd shell, there is a set of p   orbitals  There are 3 choices for the magnetic quantum ...
l = 1m = -1, 0, 1S = +1/2 , -1/2
2 px
2py
2pz
px   py   pz
Electronic configuration of elementsRules for electronic configuration:   The Pauli Exclusion principle:   Only two electr...
Hunds Rule:   Electrons prefer parallel spins in separate   orbitals of subshells  The Aufbau Principle:   Explains the or...
The energy relationships among the first threelevels of orbitals;
1s   2s   3s   4s   5s   6s   7s     2p   3p   4p   5p   6p   7p          3d   4d   5d   6d
Example : Write a complete electronic configuration for the noble gases;                  He, Ne, Ar, Kr, Xe,Solution:    ...
He2    1s2Ne10   1s2 2s2 2p6Ar18   1s2 2s2 2p6 3s2 3p6Kr36   1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6Xe54   1s2 2s2 2p6 3s2 3p6 4s...
Or can be shown in the box representation asshown below :         1s  He2         1s   2s    2p  Ne10         1s   2s     ...
Example :Write a complete electronic configuration for eachof the eight elements; from Na to Ar:         Na11    1s2 2s2 2...
Special electronic configuration:       The pairing of electrons raise the orbital energy            slightly.            ...
Tutorial (A)which of the following pair of atoms contain the same   -1     ?number of neutronsA-   C614 & C6 12B-   F919 &...
Which of the following particles does not contain -2)-         the same number of electrons as fluoride ion )FA-       Ne ...
the electronic configuration of helium atom ,boron -3atom , carbon atom & element X are given below.Which one could be the...
4-      atoms which have the same electronicconfiguration are said to be isoelectronic whichof the following is not isoele...
the magnetic quantum number )m( gives -5A- the sub shellsB- the orbitals .C- the spin of the electron
Tutorial (B)1- an orbital can take a maximum of…………..electrons.2- an) s ( sub level can take a maximum of……electrons.3- th...
which of the following orbitals could not be exist? -6.   1s,1p,1d,2s,2p,2d,3p,3d,3f,4s,4f     7- write the four quantum n...
9-    How many electrons are required to fill all the      following subshells?      1s 2s 2p 3s 3p 4s 3d 4p10-    Which o...
11- Which of the following two electronicconfigurations is more stable?   a [Ar]4s2 3d9   b [Ar]4s1 3d1012- Choose the ele...
The Periodic Table of Elements     By the late 1800s many elements had     already been discovered.      The scientist Dmi...
Periodic law:The modern periodic law states that ; when elementsare arranged by atomic number; their physical andchemical ...
The periodic table displays the elements in rows   )periods ( and columns in order of increasingatomic number.   Elements ...
From the periodic table we can know many informationdirectly like symbol, atomic number, atomic mass & youcan also know wh...
All elements in each group have the same number ofelectrons in their outer most shells so the behave similarly.We have two...
Metals : are found on the left-hand and at the centre ofthe periodic tableNon metals: are relatively few they are in the u...
Group 1A metals )Li, Na, K, Rb, Cs, and Fr( are calledthe alkali metals , and they are the most reactive metalsin the peri...
Group 1B )Cu, Ag and Au( are called the coinage metalsAlthough these elements have outer electronicconfiguration similar t...
Physical properties of elementsIonization Energy )I(:Is the energy required to remove an electron from anisolated atom in ...
Chemical Bonds:In nature elements or compounds exist due tocombination of similar or different atomsAtoms and molecules ar...
 Metals: have three or less electrons  e.g. Na, Ca, Fe Nonmetals: Have five or more electrons  e.g. H, N, S Carbon atom...
The Bonds By which atoms can combine are :   Ionic Bond   Covalent Bond   Co-ordinate Bond
Ionic BondThis is Characteristic of metallic and non metalliccombination forming a neutral molecule. It is achieved via tw...
   Ionization of atoms:                      +              -Na                   Na    +     e                          ...
 Formation     of the molecule In formation of molecules, loss or gain of electron occurs at the same time.
e.g. Formation of NaCl:                                 +        Na                                   -                   ...
Thus two ions of different charges of equal numberareformed, attraction between them taken place, leadingto the formation ...
Example:Formation of CaCl2 ;                               ++              -      Ca                      Ca    +     2e  ...
Covalent Bond   The covalent bond is the chemical bond in which   two or more non metal atoms share electrons    Both at...
 e.g. Fluorine atom has 7 electrons in its outermost  shell. It needs one electron to reach its octet. To achieve this F...
F   +   F                    F      F        F      F               F2            Single Covalent Bond
Examples:Water molecule:H+H         +     O              H O      H                H O H                    H2O           ...
Ammonia molecule: N    +   3H               H    N   H                                H               H    N H            ...
Oxygen molecule: O    +   O              O     O          O    O             O2              Double Covalent Bond
Nitrogen molecule:  N +     N                 N         N           N     N               N2               Triple Covalent...
Co-ordinate BondCoordinate covalent bonding is a special type ofbonding, in which the bonding electrons originatesolely fr...
e.g. SO2 molecule:O + O + S                      O     S     O          O     S    O             SO2               Co-ordi...
Atomic Structure
Atomic Structure
Atomic Structure
Atomic Structure
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Atomic Structure

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  • n,l, m, s
  • Shell collection of orbital's
  • Atomic Structure

    1. 1. Atomic Structure
    2. 2. The Structure of the AtomThe AtomAtoms are basic building blocks ofmatter, and cannot be chemicallysubdivided by ordinary means.
    3. 3. in 1808 John Dalton (an Englishscientist) states a theory about thenature of the elements known asDalton’s atomic theory , the mainideas of this theory can be statedas follows:
    4. 4. Elements are made of a tiny particlecalled an atom. All atoms of a given element areidentical.The atoms of a given element aredifferent from those of any otherelement.
    5. 5. Atoms of one element can combinewith atoms of other elements to form compounds. In chemical reactions atoms are neither created nor destroyed they simply change the way they are grouped together.
    6. 6. Later on Thomson & Rutherformed worked on the structure of the atom & they discovered that the atom isconsist of a tiny nucleus ( about 10-13 cm indiameter) and electrons that move around thenucleus . The nucleus contains protons whichhave a positive charge equal in magnitude tothe electrons negative charge , and neutrons ,which have almost the same mass as a protonbut no charge.
    7. 7. Atoms are composed of three type of particles: Protons Neutrons Electron
    8. 8. The mass & charge of the electron, proton & neutron are given below: particle Relative Relative mass charge electron 1 1- proton 1836 1+ neutron 1839 No charge
    9. 9. Modern atomic theory: In 1911 Niels Bohr construct a model of the hydrogen atom with quantized energy levels , Bohr picture the electrons moving in circular orbits (like planetorbiting the sun) , corresponding to thevarious allowed energy levels. He suggestedthat the electron could jump to different orbitby absorbing or emitting energy.
    10. 10. Bohr’s atomic orbital:• Is a specific path on which the electrons travel about the nucleus. - - - +
    11. 11. Although Bohrs model opened the way for the later theories it isimportant to realize that electrons donot move around the nucleus incircular orbits like the planet orbitingthe sun.
    12. 12. Later on Schrodinger found that it is not precisely to describe theelectrons path , he could only predictthe probability of finding the electronat a given point in space around thenucleus .
    13. 13. • In its ground state the hydrogenelectron has a probability map The probability map, or orbital that describes the hydrogen electron in its lowest possible energy state . The more intense the color of agiven dot the more likely it is that theelectron will be found at that point.
    14. 14. Shrodinger showed that the orbitals of electrons are regions of electron density with the location and routsof electrons described asprobabilities.
    15. 15. Isotopes:Atoms with the same number ofprotons but different number ofneutrons. In nature elements areusually found as a mixture ofisotopes.
    16. 16. Hydrogen 1 (hydrogen)   Hydrogen 2 (deuterium)   Hydrogen 3 (tritium) 1 proton, 0 neutrons 1 proton, 1 neutron 2 neutrons Mass number = 1 Mass number = 2 Mass number = 3
    17. 17. ExampleThree isotopes of elemental carbonare C612 , C613, C614 . Determine thenumber of each of the three types subatomic particles in each of thesecarbon atoms.
    18. 18. Atomic number:The number of protons in the nucleus.Mass number:The sum of the number of neutrons &number of protons in a given nucleus.
    19. 19. Ions: • Under certain circumstances it is possible to remove electrons from a neutral atom leaving a positively charged particle (cation) . • Electrons may be added to a certain atoms to form a negatively charged particle (anion). These charged particles whether positive or negative are called ions.
    20. 20. Atomic OrbitalQuantum numbers:     The various orbitals available to an atom are described by four quantum numbers, which can take certain values to create differently sized and shaped orbital of various energies:
    21. 21. The principal quantum number (n)describes the: Shells:(an electron shell is collection of orbitals)  Size of orbital  Numbered 1, 2, 3, 4, 5, etc  are often lettered (K, L, M, etc.).
    22. 22. The subsidiary quantum number (l)describes the: Subshells : are groups of orbitals with in an electron Shape of orbital (number of lobes). Given letters s, p, d, f, g, h, i, etc. The values of ( l ) run from 0 to n − 1
    23. 23. The magnetic quantum number (m)describes: Orientation of the orbitals in space. Named after the directions they point in (x, y, z, etc.) Can also be given numbers ranging from 0, ±1, ±2, ±3 … ±l.
    24. 24. The spin quantum number (s). describes: spin of an electron on its own axis May have the values +½ or -½. Two electrons in the same orbital have paired (opposite) spins 
    25. 25. The Quantum Numbersname symbol valuesPrincipal QuantumNumber n any integer from 1 to infinitySubsidiary QuantumNumber l any integer from 0 to n-1Magnetic QuantumNumber m any integer from - l to+ lSpin QuantumNumber s 1/2 -/+
    26. 26. orbital Max no. ofL-value No. of orbitals type electrons 0 s 1 2 1 p 3 6 2 d 5 10 3 f 7 14
    27. 27. Using symbols, the valid quantumstates can be listed in the followingmanner: 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 7h 7s 7p 7d 7f 7g 7h 8i
    28. 28. Atomic Orbitals The S Orbital The simplest orbital in the atom is the 1s orbital. The 1s orbital is simply a sphere of electron density. There is only one s orbital per shell The s orbital can hold two electrons have different spin quantum numbers l = 0 m = 0 S = +1/2 , -1/2
    29. 29. 1s Shell
    30. 30. The P Orbitals Starting from the 2nd shell, there is a set of p orbitals There are 3 choices for the magnetic quantum number, which indicates 3 differently orientated p orbitals px, py, and pz each orbital can accommodate two electrons, giving a total capacity of 6 electrons. p orbitals are very often involved in bonding 
    31. 31. l = 1m = -1, 0, 1S = +1/2 , -1/2
    32. 32. 2 px
    33. 33. 2py
    34. 34. 2pz
    35. 35. px py pz
    36. 36. Electronic configuration of elementsRules for electronic configuration: The Pauli Exclusion principle: Only two electrons with opposite spin can occupy an atomic orbital (or no twoelectrons have the same (4) quantumnumbers n, l, m and s) 1s
    37. 37. Hunds Rule: Electrons prefer parallel spins in separate orbitals of subshells The Aufbau Principle: Explains the order in which the electrons fill the various orbitals in an atom. Filling begins with the orbitals in the lowest- energy shells and continues through thehigher-energy shells
    38. 38. The energy relationships among the first threelevels of orbitals;
    39. 39. 1s 2s 3s 4s 5s 6s 7s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d
    40. 40. Example : Write a complete electronic configuration for the noble gases; He, Ne, Ar, Kr, Xe,Solution: This can be written in the normalconfiguration representation As shownbelow:
    41. 41. He2 1s2Ne10 1s2 2s2 2p6Ar18 1s2 2s2 2p6 3s2 3p6Kr36 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6Xe54 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6
    42. 42. Or can be shown in the box representation asshown below : 1s He2 1s 2s 2p Ne10 1s 2s 2p 3s 3p Ar18
    43. 43. Example :Write a complete electronic configuration for eachof the eight elements; from Na to Ar: Na11 1s2 2s2 2p6 3s1 or [Ne] 3s1 Mg 12 1s2 2s2 2p6 3s2 [Ne] 3s2 Al13 1s2 2s2 2p6 3s2 3p1 [Ne]3s2 3p1 Si14 1s2 2s2 2p6 3s2 3p2 [Ne] 3s2 3p2 P15 1s2 2s2 2p6 3s2 3p3 [Ne] 3s2 3p3 S16 1s2 2s2 2p6 3s2 3p4 [Ne] 3s2 3p4 Cl17 1s2 2s2 2p6 3s2 3p5 [Ne] 3s2 3p5 Ar18 1s2 2s2 2p6 3s2 3p6 [Ne] 3s2 3p6
    44. 44. Special electronic configuration: The pairing of electrons raise the orbital energy slightly. Half-filled and full-filled subshell low the energy. For example the electronic configuration of Cr and 1sCu 2s 2p 3s 3p 4s 3dCr24 1s 2s 2p 3s 3p 4s 3dCu29
    45. 45. Tutorial (A)which of the following pair of atoms contain the same -1 ?number of neutronsA- C614 & C6 12B- F919 & Ne1022C- S1632 &Al1329
    46. 46. Which of the following particles does not contain -2)- the same number of electrons as fluoride ion )FA- Ne B- + Li+ C- Na
    47. 47. the electronic configuration of helium atom ,boron -3atom , carbon atom & element X are given below.Which one could be the electronic configuration ofelement X?A- 1s2 2s22P1B- 1s2C- 1s2 2s 1D- 1s2 2s2 2p2
    48. 48. 4- atoms which have the same electronicconfiguration are said to be isoelectronic whichof the following is not isoelectronic with O2-? A- N 3- B- Al 3+ C- Na + D- Na
    49. 49. the magnetic quantum number )m( gives -5A- the sub shellsB- the orbitals .C- the spin of the electron
    50. 50. Tutorial (B)1- an orbital can take a maximum of…………..electrons.2- an) s ( sub level can take a maximum of……electrons.3- the )p( sub level can take a maximum of…….electrons.4- how many electrons can fit in to a set of )5d( orbitals?5- what is the maximum numbers of electrons in levels, 2, 3, 4 ?
    51. 51. which of the following orbitals could not be exist? -6. 1s,1p,1d,2s,2p,2d,3p,3d,3f,4s,4f 7- write the four quantum numbers for energy level)4(? 8- For the H-like atom, which subshell has the highest energy level? 4f, 3d, 2p, 1s
    52. 52. 9- How many electrons are required to fill all the following subshells? 1s 2s 2p 3s 3p 4s 3d 4p10- Which of the following two electronic configuration is more stable? a- [Ar]4s1 3d5 b- [Ar]4s2 3d4
    53. 53. 11- Which of the following two electronicconfigurations is more stable? a [Ar]4s2 3d9 b [Ar]4s1 3d1012- Choose the electronic configuration for palladium, Pd )Z = 46(. a- [Kr]5s1 4d7 b- [Kr]5s1 4d8 c- [Kr]5s0 4d10 d- [Kr]5s1 4d10
    54. 54. The Periodic Table of Elements    By the late 1800s many elements had already been discovered.    The scientist Dmitri Mendeleev, a Russian chemist, proposed an arrangement of known elements based on their atomic mass   The modern arrangement of the elements is known as the Periodic Table of Elements and is arranged according to the atomic number of elements.
    55. 55. Periodic law:The modern periodic law states that ; when elementsare arranged by atomic number; their physical andchemical properties vary periodically .
    56. 56. The periodic table displays the elements in rows )periods ( and columns in order of increasingatomic number. Elements that have similar chemical properties fall into vertical columns called groups or families Most of the elements are metals and located on the left hand side of the periodic table The nonmetals appear on the right hand side of the periodic table
    57. 57. From the periodic table we can know many informationdirectly like symbol, atomic number, atomic mass & youcan also know whether the element is metal, non metalor metalloid.Todays periodic table consist of seven horizontal rowscalled periods & a number of vertical columns calledgroups.
    58. 58. All elements in each group have the same number ofelectrons in their outer most shells so the behave similarly.We have two types of groups:Group )A(: ) representative or main elements(Group )B(:) transition elements(
    59. 59. Metals : are found on the left-hand and at the centre ofthe periodic tableNon metals: are relatively few they are in the upper-righthand corner the tableMetalloids : those are few elements exhibit both metallicand nonmetallic behavior )also known as semimetals(
    60. 60. Group 1A metals )Li, Na, K, Rb, Cs, and Fr( are calledthe alkali metals , and they are the most reactive metalsin the periodic table.Group 2A metals )Be, Mg, Ca, and Ra( are called thealkaline earth metals.
    61. 61. Group 1B )Cu, Ag and Au( are called the coinage metalsAlthough these elements have outer electronicconfiguration similar to those of the alkali metals and thealkaline earth metal the are much less reactiveGroup 7A )F, Cl, Br and I( are called halogens and theyare the most reactive nonmetals in the periodic tableGroup 8A )He, Ne, Ar, Kr, Xe, and Rn( are called therare or noble gases,these gases are characteristic by their completely filledshells, for this reason they are chemically inert.
    62. 62. Physical properties of elementsIonization Energy )I(:Is the energy required to remove an electron from anisolated atom in its ground state.X)g(
    63. 63. Chemical Bonds:In nature elements or compounds exist due tocombination of similar or different atomsAtoms and molecules are electrically neutral, accordingto this fact in atom combination each tries to exhibit 8electrons on the outer most shell that by loosing,gaining or sharing electrons.
    64. 64.  Metals: have three or less electrons e.g. Na, Ca, Fe Nonmetals: Have five or more electrons e.g. H, N, S Carbon atom: have four electrons in the outer most shell liable to loose them or to gain more electrons
    65. 65. The Bonds By which atoms can combine are :  Ionic Bond  Covalent Bond  Co-ordinate Bond
    66. 66. Ionic BondThis is Characteristic of metallic and non metalliccombination forming a neutral molecule. It is achieved via two steps:  Ionization of atoms  Formation of the molecule 
    67. 67.  Ionization of atoms: + -Na Na + e Cations ++ -Ca Ca + 2e - - Cl + e Cl Anions -- S + 2e S
    68. 68.  Formation of the molecule In formation of molecules, loss or gain of electron occurs at the same time.
    69. 69. e.g. Formation of NaCl: + Na - Na + e Chlorine atom attacks this electron to its outermost shell and become an anion. - - Cl + e Cl
    70. 70. Thus two ions of different charges of equal numberareformed, attraction between them taken place, leadingto the formation of the neutral molecule NaCl. + - Na + Cl NaCl  NaCl is said to be ionic compound 
    71. 71. Example:Formation of CaCl2 ; ++ - Ca Ca + 2e - - Cl + e Cl - ++ Cl Ca + - CaCl2 Cl
    72. 72. Covalent Bond   The covalent bond is the chemical bond in which two or more non metal atoms share electrons    Both atoms are unable to loose or gain electrons    By sharing electrons both atoms reach octet state
    73. 73.  e.g. Fluorine atom has 7 electrons in its outermost shell. It needs one electron to reach its octet. To achieve this F atom shares an electron belonging to another F atom By this F2 molecule is formed
    74. 74. F + F F F F F F2 Single Covalent Bond
    75. 75. Examples:Water molecule:H+H + O H O H H O H H2O Single Covalent Bond
    76. 76. Ammonia molecule: N + 3H H N H H H N H NH3 H Single Covalent Bond
    77. 77. Oxygen molecule: O + O O O O O O2 Double Covalent Bond
    78. 78. Nitrogen molecule: N + N N N N N N2 Triple Covalent Bond
    79. 79. Co-ordinate BondCoordinate covalent bonding is a special type ofbonding, in which the bonding electrons originatesolely from another atom.
    80. 80. e.g. SO2 molecule:O + O + S O S O O S O SO2 Co-ordinate Covalent Bond

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