September 30, IB Syllabus. So, here's the order and you will have to memorize the order! But we can also use the periodic table!

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1 So, here's the order and you will have to memorize the order! 1 H Hydrogen 3 4 Li Na Be Lithium Beryllium Mg Sodium Magnesium But we can also use the periodic table! B Al C Si N P O S F Cl 2 He Helium Ne Boron Carbon Nitrogen Oxygen Fluorine Neon Ar Aluminium Silicon Phosphorus Sulfur Chlorine Argon K Ca Potassium Calcium Sc Ti V Cr Mn Fe Co Ni Cu Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Zn Ga Ge As Se Br Kr Gallium Germanium Arsenic Selenium Bromine Krypton Rb Sr Rubidium Strontium Y Zr Nb Mo Tc Ru Rh Pd Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Ag Cd In Sn Sb Te I Xe Cs Ba Cesium Barium La Hf Ta W Re Os Lanthanum Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury Ir Pt Au Hg Tl Pb Bi Po At Rn Thallium Lead Bismuth Polonium Astatine Radon Fr Ra Francium Radium Ac Rf Db Sg Bh Hs Mt Actinium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium 58 Ce 59 Pr 60 Nd 61 Pm 62 Sm 63 Eu 64 Gd 65 Tb 66 Dy 67 Ho Er 69 Tm 70 Yb 71 Lu 68 Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Th 91 Pa U 93 Np 94 Pu 95 Am 96 Cm 97 Bk 98 Cf 99 Es 100 Fm 101 Md 102 No 103 Lr Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium IB Syllabus Application of the Aufbau principle, Hund s rule and the Pauli exclusion principle to write electron configurations for atoms and ions up to Z = 36.?

2 Review: Let's try this one. State the electron configuration of tellurium. What about ions? Ba 2+ Cl - What about Cr? What about Cr?

3 Another one:? Exceptions: Here are some questions for you to try! How do we know if the sub orbitals are actually there? Well, from the ionization energy patterns! So, what's ionization energy? The first electron to be removed is one that already has a high energy and is least strongly attracted to the nucleus; that is, one in the valence shell. This will require the lowest ionization energy. If there are more electrons in this outer shell, then they will be removed next, with the ionization energy gradually increasing. When the outermost electron shell is empty, the next electron to be lost will come from the next closest shell to the nucleus. But since this shell is full, and therefore stable, a great deal more energy will be required to remove one electron from this shell than was needed to remove the previous electron.

4 A graph of first ionization energies of the first 54 elements shows distinct patterns that lead us to a greater understanding of the electron structure of an atom. The most obvious feature of this graph is the periodic series of peaks corresponding to the first ionization energy of the noble gases (He, Ne, Ar, Kr, Xe). These elements have high first ionization energies because they have a full electron shell and an associated high degree of energetic stability. The next most obvious feature of the graph is the lowest point of each periodic series. These troughs correspond to the group 1 elements (Li, Na, K, Rb). These elements have only one electron in the outer shell and so the first ionization energy is small, as little energy is required to remove this electron from the atom. But, let's examine further... If the second energy level is like the first energy level, then we would expect a gradual increase in ionization energy as we remove the electrons one by one However, that's not the case!

5 This suggests the presence of sub-levels (subshells) within the main energy levels. The first sub-level in the 2nd energy level is filled with 2 electrons. The second sub-level appears to be filled by 3 electrons, with a third sub-level filled with a further 3 electrons. The other possibility, is that the second sub-level gains some stability in becoming half-full, and its greatest stability is when it is completely full with 6 electrons in it. So, what are these s, p, d, f orbitals? An orbital is a region of space in which an electron or electrons may be found Draw the shape of an s orbital and the shapes of the px, py and pz orbitals. s orbitals P orbitals What about d?

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