Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Agenda 11/7/2016 9:15 - 10:25 Slip Quiz Trends in Properties in the Periodic table explaining the patterns (notes from slides) Demonstration: Flame tests Additional Review Questions for test Homework Slip Quiz 1 Which of the following has 8 valence electrons? Explain how you decided. antimony, aluminum, argon, arsenic. 2. Which 2 elements in the list would have the same number of valence electrons? How many? How do you know? Correct your answers Which of the following has 8 valence electrons? Explain how you decided. antimony, aluminum, argon, arsenic. Argon has 8 valence electrons - group 18 2 2 6 2 6 2 6 1s 2s 2p 3s 3p [Ne]3s 3p 8 electrons in outermost energy level orbitals antimony, aluminum, argon, arsenic. Antimony and arsenic are in the same group (Grp 15) in the Periodic table and all elements in a group have same number of valence electrons. As electron config. [Ar]3d104s24p3 5 valence electrons This 2D model is useful for thinking about the size of atoms and how they might change along periods and down groups in the periodic table e-e(showing electrons in Energy levels, increasing ee- e- 11+ eeeIn energy as the levels ee- eIncrease in size). Atomic radius vs. Atomic Number (take notes under graph) Generally Atomic radius increases down a group Generally Atomic radius increases down a group Generally Atomic radius increases down a group Generally Atomic radius decreases across a period Generally Atomic radius decreases across a period Generally Atomic radius decreases across a period Note on atomic radius - measuring it Atomic radius vs. ionic radius An ion is an atom or bonded group of atoms that has a positive or negative charge. Atomic radius e- 11+ eeLarger ee- eee- ethan e-e- Ionic radius Sodium atom Sodium ion Na+ Electrically neutral 11+ - 10- = +1 charge Periodic Variation in Chemical Properties Ionization energy Periodic Variation in Chemical Properties p 167 Generally ionization energy _______ down a group p 167 p 167 p 167 Generally ionization energy decreases down a group Generally ionization energy ____________ across a period p 167 Generally ionization energy increases across a period The Octet Rule Atoms tend to gain, lose or share electrons in order to acquire a full set of eight valence electrons. Electron configurations like those of the Noble gases with filled s and p orbitals of the same energy level are unusually stable. (Note that Helium has only 2 valence electrons, but that is because the 1st energy level can only accommodate 2 electrons in its 1s orbital.) The Octet Rule Electron configurations like those of the Noble gases with filled s and p orbitals of the same energy level are unusually stable. (Note that Helium has only 2 valence electrons, but that is because the 1st energy level can only accommodate 2 electrons in its 1s orbital.) Useful for determining the type of ions that elements are likely to form. Keep the IUPAC announcement safe for now. 115 Ds Rg Cn Nh Fl Mc 116 Lv 117 118 Ts Og a) a) a) a) Hund’s rule: single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins occupy the same orbitals. a) a) a) a) : : a) b) • c) • • • • ☉ Homework Test is 20 multiple choice 1 pt each 5 Structured - total 65 pts (Includes Graphing question). Chapters 6 and 5. Test on Wednesday, Nov 9th.