Electron configuration-2.2

continuous spectrum vs. line spectrum violet- 410 nm blue- 434 nm blue-green- 486 nm red- 656 nm

Emission spectrum of hydrogen consists of a series of lines of different colors N=1, 2, 3, 4, 5, 6 Violet transitions from n=6 to n=2 Blue transitions from n=5 to n=2 Blue-green transitions from n=4 to n=2 Red transitions from n=3 to n=2 light can’t be seen under 400 nm (n=1)

Energy States Ground-state and excited-state Photon- discrete amount of energy -When electron falls down from excited state light is emitted different color lights, dependent on wavelength (energy released)

Sublevels (orbitals) s, p, d, f Maximum number of electrons in sublevels (orbital) s- 2 (99% chance of finding electron) p- 6 (Px, Py, Pz three atomic orbitals) d- 10 (five orbitals) f- 14 (seven orbitals)

Orbitals every orbital can only contain/hold a maximum of 2 electrons, with opposite spins example: electrons fill at the lowest-energy orbital first before the next (s, p, d, and then f)

isoelectronic series

Electron Configuration-looks like fill in the s orbital first, then p, then d, and finally f if needed. example: k (potassium) z=19 1s2 2s2 2p6 3s2 3p6 4s1 (keep in mind that 4s fills before 3d) Z represents the atomic number (number of protons) anion add electrons, cation remove electrons

Blocks on the periodic table main group elements: 1-2 & first element on 18 (helium): s block 3-12: d block 13-18: p block f block at the bottom *knowing the blocks will save you time when writing out the electron configuration*

Condensed electron configuration [ nearest noble gas] + valence electrons example: Br 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p5 alternative [Ar] 3d10 4s2 4p5 useful when there is an element w/ a lot of electrons

practice problems Write the full electron configuration of Si (silicon), z=14 Draw an orbital diagram of N (nitrogen), z=7 Write the condensed electron configuration of Zn (zinc), z=30 Write the condensed electron configuration of As2- (arsenic), z=33 In the emission spectrum of hydrogen, which electronic transition would produce a line in the visible region of the electromagnetic spectrum? (from IB textbook) A. n=2 n=1 B. n=3 n=2 C. n=2 n=3 D. n=∞ n=1

Answers 1s2 2s2 2p6 3s2 3p2 5. B, because energy level is decreasing, light is emitted 2. 3. [Ar] 4s2 3d10 4. [Ar] 4s2 3d10 4p1 2p 2s 1s