04CHM114_0218

04CHM114_0218 - CHEM 114 Spring 2004 wed. Feb.18th lecture...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CHEM 114 Spring 2004 wed. Feb.18th lecture No.13 Exam 1, on Friday: Coverage: all chapters up to, and including 6.3. Last day, started to build atoms using the hydrogen atom energy level scheme, ‘ THE MULTIELECTRON ATOM AND THE PERIODIC TABLE. Here the idea is to preserve the energy level scheme worked out for the hydrogen atom (assume the same scheme applies to atoms with more than one proton at the center and an equal number of electrons to neutralise the positive charge). _ The we find out where the electrons are by adding the total elctron count according to rules, as follows: 1. e‘ go into the lowest energy levels available 2. The individual orbitals can only hold two e- maximum (Pauli exclusion principle: no two e- can have the m same four q.n) 3. When orbitals are degenerate, the e- occupy them singly till all are half—filled (Hund's rule of "maximum multiplicity'l..." UGH! I I) O. K. let's go! Electronic fowl; 3. Li (alkali metal) shielding of nuclear charge (Moseley) Text section 7.2. 3 + 3+ The 25 electron on lithium is loosely bound... roughly four time further from the nucleus than in hydrogen, and attracted by an effective] charge that is barely more than in the case of h r en, because of the shielding....s 4.Be Ln" 2"“- 5.1-5 1-: 5.B paramagnetism.. what is it? ‘ n Mo.th c-M‘w. P.1u.1 owl-um: Iw‘l'o 0- must»th ‘ 4"“ - Am. (‘0 shape-mus Irma- How will it change as we change the atomic number? (Hand’s rule in action) 6. C 6f” (¢) > Ce. 7. N (the most paramagnetic in the first complete row (why?) 8.0 out.) a, . P 9. unpuéd 391;! .3 law!» 0-4 3 on. M . t;- m‘ 9. F 1 V I‘- 5 s c 10. Ne second shell complete: inert gas 9. fluorine. why it is so reactive 10. neon "no knobs" because three filled p orbital electron densities sum to a symmetric shell that looks like an s orbital L‘h- H‘, lfi;ri- “fiasco-“:1 an— " NUCL!‘ a”. Third row 11 Na alkali metal: shielding of nuclear charge again. (see Fig. 7.3). Na has 11 protons but 1822822136 4 shields the nucleus so well that theésrl electron only "feels" a positive charge of Z (effective) g1ven by But e- is far from nucleus, so attraction is very weak. compare with Lithium (Table) I; M IZATION ENERGY AND THE ENERGY OF THE ELECTRON ENERGY 0K. Let's fill the third shell. Mg Electronic formulas: list electrons in subshells in order of increasing energy for Mg: 132232226332 01‘ A1: Si: P: M“IMWH; thV-a MA‘W'“ Hund's rule again: half filled shell m S Cl, and Sa ‘ 1 ‘1: F.“ UM“, Ar (inert gas again) Now some problem (45 level lies at lower energy than 3d) so next element is again an alkali metal Le. an element with a single electron in an s orbital. TAKE A BREAK... SEE WHY IT IS CALLED A PERIODIC TABLE. (The problem with the word "periodic") W p IONIZATION ENERGY A OMIC NUMBER 7 Question: ( him-J c1: (- k: "0“) Which of the following ia periodic function of atomic number . A. density B. Ionization energy C. Atomic volume D. Atomic weight E. Melting point At. "‘- ( “i: M peek-bu + Haircut M. No. (M of Pun-Ivan!) OK. Back to building: K: 451 Ca: (Ar)4sZ Sc: (Ar)4823d1 Ti: (Ar)4sz3d2 (solar cells) ...
View Full Document

Page1 / 8

04CHM114_0218 - CHEM 114 Spring 2004 wed. Feb.18th lecture...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online