02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Atomic Theory and the Periodic Table "I'm old and a little scary...but I created the periodic table so WHAT UP NOW?!?! Sep 8­8:04 AM (D) (A) (C) (E) (B) Sep 8­8:11 AM Particle Proton Neutron Electron Mass Charge Atomic Number = Atomic Weight = Ionic Charge = What is an isotope? Sep 8­8:12 AM 1 02 ­ Atomic Theory and Perioidicity.notebook Symbol August 09, 2018 121 Sb Protons 45 Neutrons 58 50 38 Electrons Mass # Sep 8­8:12 AM Symbol 75 As3­ Protons 28 53 Neutrons 31 74 Electrons 26 1­ Oxidation # Sep 8­8:12 AM Mass Spectroscopy What element is this? How many isotopes does this element have? What is the average atomic mass of this element? What is an isotope? Sep 3­8:42 AM 2 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 24. Element X is found in two forms: 90.0% is an isotope that has a mass of 20.0, and 10.0% is an isotope that has a mass of 22.0. What is the atomic mass of element X? (A) 20.0 (B) 20.2 (C) 20.8 (D) 21.2 (E) 21.8 Sep 8­8:34 AM Determine how many valence electrons and unpaired electrons for: unpaired valence electrons electrons (a) nitrogen (b) magnesium (c) chlorine (d) boron Sep 8­8:13 AM Write the abbreviated electron config for: (a) sodium (b) sulfur (c) iron (d) Ag+ (f) Cl­ Sep 8­8:12 AM 3 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Write the abbreviated electron config for: (a) Zn2+ (b) O2­ (c) What is one element and one ion that O2­ is isoelectronic with? Sep 8­8:12 AM Sep 8­8:12 AM Sep 8­8:38 AM 4 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Sep 8­8:32 AM Diamagnetic Paramagnetic Fe Colored as a solution Cu Zn Cr Sep 8­8:32 AM Sep 8­8:58 AM 5 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Flame Test Colors Na+ Li+ K+ Cu2+ Sep 12­7:59 AM c=λυ speed of light = wavelength x frequency speed of light = 3 x 108 m/s E=hυ Energy = Planck's constant x frequency Planck's constant = 6.63 x 10­34 J sec Sep 12­8:01 AM Mass Spectroscopy Photoelectron Spectroscopy Sep 9­7:47 AM 6 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 All Periodic Trends can be explained using three basic principles: 1. Electrons are attracted to the protons in the nucleus. (Zeff = effective nuclear charge) (a) The closer the electron is to the nucleus, the more strongly it is attracted. (b) The more protons in the nucleus, the more strongly the electron is attracted Sep 13­7:54 AM All Periodic Trends can be explained using three basic principles: 2. Electrons are repelled by other electrons. (a) Valence electrons are shielded by completed shells of electrons. Sep 13­7:54 AM All Periodic Trends can be explained using three basic principles: 3. Completed shells are very stable. Atoms will lose or gain valence electrons to created completed shells if possible. Sep 13­7:54 AM 7 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Attacking Atomic Theory Statements #1 Determine what the elements or compounds have in common. #2 Determine what the elements or compounds differ in. #3 Go to your principles to explain the difference clearly and concisely. Sep 13­8:03 AM Explain each in terms of principles of atomic structure (a) Fluorine has a smaller atomic radius than lithium (b) Rubidium has a larger atomic radius than sodium Sep 13­8:05 AM Explain each in terms of principles of atomic structure (a) Cl­, Ar, and K+ are isoelectronic. Which has the smallest radius and why? Which has the biggest and why? (b) State the trend for atomic radius in going across a period from left to right and why. Sep 13­8:05 AM 8 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Explain each in terms of principles of atomic structure (a) Potassium has a lower first ionization energy as compared to lithium. (b) Sodium has a lower first ionization energy as compared to sulfur. Sep 13­8:05 AM Explain each in terms of principles of atomic structure (a) O or O2­. Which is larger and why? (b) Potassium has a low first ionization energy but a relatively large second ionization energy. Sep 13­8:05 AM Explain each in terms of principles of atomic structure (a) Why is the second ionization energy always larger than the first? (b) Write the chemical reaction showing the first ionization energy of sodium. Sep 13­8:05 AM 9 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Explain each in terms of principles of atomic structure (a) The difference between the first and second ionization energies of sodium is much larger than the difference between the first and second ionization energies of magnesium. (b) What element could this be. Explain. 1st IE = 540 kJ, 2nd IE = 1000 kJ, 3rd IE = 1700 kJ, 4th IE = 5400 kJ, 5th IE = 5950 kJ Sep 13­8:05 AM Explain each in terms of principles of atomic structure (a) Boron has a smaller first ionization energy than beryllium. (b) Write a chemical reaction for the electron affinity of fluorine. (c) The electron affinity for chlorine is negative whereas for argon it is positive. Sep 13­8:05 AM Explain each in terms of principles of atomic structure (a) Cesium is much more reactive in the presence of water as compared to lithium. (b) The difference between the atomic radii of lithium and sodium is relatively smaller than the difference between the atomic radii of rubidium and cesium. Sep 13­8:05 AM 10 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Explain each in terms of principles of atomic structure (a) A sample of solid nickel chloride is attracted into a magnetic field whereas a sample of solid zinc chloride is not. (b) Phosphorous forms fluorides of PF3 and PF5 whereas nitrogen only forms NF3. Sep 13­8:05 AM Answer the following questions about the element selenium, Se (atomic number 34). (a) Samples of natural selenium contain six stable isotopes. In terms of atomic structure, explain what these isotopes have in common, and how they differ. (b) Write the complete electron configuration (e.g., 1s2 2s2 … etc.) for a selenium atom in the ground state. Indicate the number of unpaired electrons in the ground­state atom, and explain your reasoning. (c) In terms of atomic structure, explain why the first ionization energy of selenium is (i) less than that of bromine (atomic number 35), and (ii) greater than that of tellurium (atomic number 52). Sep 20­11:18 AM 11 02 ­ Atomic Theory and Perioidicity.notebook August 09, 2018 Sep 14­7:58 AM Sep 19­11:20 AM Use only a periodic table, individually write the following explanations using your theory of atomic principles 1) Predict which element, Na or K, has a larger first ionization energy and explain your choice. 2) Sulfur has a smaller radius than Phosphorous. Explain this trend. Sep 17­8:52 AM 12
