Unit 2 Atomic Theory and Periodicity Review

Transcription

1 Unit 2 Atomic Theory and Periodicity Review Section I: History In each box, write the name of the scientist(s) associated with the statement. Choose from among the following: Democritus Thomson Bohr Schroedinger and Heisenberg There are small negatively charged particles inside an atom Thomson There is a small, dense, positively charged nucleus Most of an atoms mass is in the nucleus Electrons follow a definite path but can jump from one path to another Bohr Atoms are mostly empty space Atoms of one element are all the same, but atoms of different elements are different Electron paths cannot be defined for certain Schroedinger and Heisenberg His discovery was made after conducting an experiment with gold foil Atoms are small, hard spheres Electrons are found in electron clouds, not in defined paths Schroedinger and Heisenberg Elements combine is specific proportions to make compounds Atoms are uncuttable Democritus His theory of atomic structure led to the plum pudding model of atoms Thomson All substances are made of atoms Section II: Atomic Vocabulary (unscramble) 1. Weighted average of all naturally occurring isotopes of the same element. (mictoa sams) atomic mass 2. The building blocks of matter (moats) atoms 3. Positively charged particle in an atom (torpno) proton 4. Made up of protons and neutrons (ucselun) nucleus 5. Particle in an atom that has no charge (tronune) neutron 6. Atoms with the same number of protons but a different number of neutrons (sootpies) isotopes 7. Negatively charged particle in an atom (cleenrot) electron 8. Number of protons in a nucleus (mictoa brumen) atomic number 9. Regions where electrons are likely to be found (renectol scudlo) electron clouds 10. Sum of protons and neutrons (sams brumen) mass number

2 Section III: Isotopes Practice Complete the table below. Complete atomic symbol Atomic # Mass # # of protons # of neutrons # of electrons 14 6 C I Cl Fe He U Name the element which has the following number of particles: a. 82 electrons, 125 neutrons, 82 protons Lead-207 b. 53 protons, 53 electrons, 74 neutrons Iodine Naturally occurring europium consists of two isotopes with masses of 151 and 153 amu. The respective abundances are 48.03% and 51.97%. What is the atomic mass of europium? amu (or g/mol) 13. Strontium consists of four isotopes. There masses and abundances are listed below. Use this data to calculate the atomic mass of strontium. Mass Abundance % % amu (or g/mol) % %

3 Section V: Unit Conversions (Mass-Moles-Atoms) 14. How many moles are in 4.14x10 22 atoms of boron? 15. Determine the mass in grams of 6.8 moles of iron mol 380 g 16. What is the mass of 1.62 x atoms of carbon? 3.23 g 17. How many atoms are in 2.17 grams of zinc? 2.00 x atoms Section VI: Regions of the periodic table 18. Name the following regions of the periodic table. a. Group IA alkali metals b. Group IIA alkaline earth metals c. Group VIIA halogens d. Group VIIIA noble gases e. Groups IB VIIIB transition metals f. The top row of the f block lanthanides g. The bottom row of the f block actinides 19. List the six metalloids (aka semimetals). Boron, silicon, germanium, arsenic, antimony, & tellurium 20. List the seven diatomic elements. hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine

4 Section VII: Electron configurations, Orbital diagrams, and Lewis dot diagrams Write the electron configurations and draw the corresponding orbital diagrams and the Lewis dot diagram for the elements below. 21. Hydrogen 1s 1 See the additional pages at the end of this 22. Boron 1s 2 2s 2 2p 1 document for orbital diagrams and electron 23. Sodium 1s 2 2s 2 2p 6 3s 1 dot diagrams. 24. Krypton 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p Chromium 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d Phosphorus 1s 2 2s 2 2p 6 3s 2 3p Carbon 1s 2 2s 2 2p Oxygen 1s 2 2s 2 2p Potassium 1s 2 2s 2 2p 6 3s 2 3p 6 4s Cobalt 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d Platinum 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 8 Write the abbreviated electron configurations and orbital diagrams for the elements below. 32. Platinum [Xe] 6s 2 4f 14 5d Plutonium [Rn]7s2 5f Neodymium [Xe]6s 2 4f Lead [Xe] 6s 2 4f 14 5d 10 6p Cesium [Xe]6s 1 Describe each of the following rules for electrons filling orbitals in an electron cloud. 37. Aufbau rule each electron occupies the lowest energy orbital available 38. Pauli exclusion principle a max of two electrons may occupy one orbital but the must have opposite spins 39. Hund s rule single electrons must occupy each equal-energy orbital before an opposite spin electron is added 40. Heisenberg uncertainty principle it is impossible to know both the velocity and position of an electron at the same time Section VIII: Periodic Trends 41. Rank the following elements by increasing atomic radius: carbon, aluminum, oxygen, potassium. O, C, Al, K 42. Rank the following elements by increasing electronegativity: sulfur, oxygen, neon, aluminum. Ne, Al, S, O 43. Rank the following elements by increasing first ionization energy: bromine, strontium, arsenic, calcium Sr, Ca, As, Br 44. Why does fluorine have a higher first ionization energy than iodine? Fluorine s valence shell is closer to the nucleus that iodine s (fluorine has fewer shielding electrons). Thus, the nucleus has a stronger attraction for fluorine s valence electrons, making them harder to remove.

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