Exam I (Fits on a Flash Card)

Exam I (Fits on a Flash Card) - 1 A nucleus consists of 17...

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1) A nucleus consists of 17 protons and 18 neutrons. What is its nuclide symbol? From the Table of Atomic Numbers and Atomic Weights, the element with atomic number 17 is chlorine, symbol Cl. The mass number is 17 + 18 = 35. The symbol is 35 17 Cl. 2) Chlorine consists of the following isotopes: Chlorine-35, Isotopic Mass (amu): 34.96885, Fractional Abundance: 0.75771, and Chlorine-37, Isotopic Mass (amu): 36.96590, Fractional Abundance: 0.24229. What is the atomic weight of Chlorine? Multiply each isotope mass by its fractional abundance, then sum: 34.96885 × 0.75771 = 26.5. 36.96590 × 0.24229 = 8.96. 26.5 + 8.96 = 35.46 amu. The atomic weight of chlorine is 35.46 amu. 3) By referring to the periodic table, identify the group and period to which each of the following elements belongs. Then decide whether the element is a metal, nonmetal, or metalloid. a. Se: group 16, period 4, nonmetal. b. Cs: group 1, period 6, metal. c. Fe: group 8, period 4, metal. d. Cu: group 11, period 4, metal. e. Br: group 17, period 4, nonmetal. 4) Potassium chromate is composed of K ¿ ¿ and 2 ¿ CrO 4 ¿ ions. Write a formula of the compound: K 2
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  • Winter '18
  • Hewage
  • Periodic Table, Chemical element, Isotope, CaO, CrO

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