University:
Seattle Pacific University
Course:
CHM 1211 | General Chemistry I
Academic year:

2022
Views:

44

Pages:

3
Author:

Alexa Livingston

CB8=B;5G=7G ANSWER KEY Section A: Complete the chart using a periodic table to help you. Element Atomic Symbol Total # of Electrons # of Valence Electrons # of Electrons Needed to Gain or Lose Oxidation Number (to Fill Outer Shell) Chlorine Cl 17 7 Gain 1 1- Potassium K 19 1 Lose 1 1+ Magnesium Mg 12 2 Lose 2 2+ Fluorine F 9 7 Gain 1 1- Aluminum Al 13 3 Lose 3 3+ Sodium Na 11 1 Lose 1 1+ Nitrogen N 14 4 Gain 3 3- Oxygen O 8 6 Gain 2 2- Hydrogen H 1 1 Gain or Lose 1 1+ or 1- Carbon C 6 4 Gain or Lose 4 4+ or 4- Iodine I 53 7 Gain 1 1- Answer these questions: An atom that gains one or more electrons will have a NEGATIVE charge. An atom that loses one or more electrons will have a POSTIVE charge. An atom that gains or loses one or more electrons is called an ION. A positive ion is called a CATION and a negative ion is called an ANION. Section B: Ionic Bonds ANSWER KEY What is an ionic bond? Atoms will transfer one or more electrons to another to form the bond. Each atom is left with a complete outer shell. An ionic bond forms between a metal ion with a positive charge and a nonmetal ion with a negative charge. Example B1: Sodium + Chlorine Example B2: Magnesium + Iodine I Na Mg Cl Na1+ + Cl1- Æ NaCl Example B3: Potassium + Iodine I Mg2+ + I1- + I1- Æ MgI2 Example B4: Sodium + Oxygen Na K I O Na K1+ + I1- Æ KI Na1+ + Na1+ + O2- Æ Na2O Example B5: Calcium + Chlorine Mg Cl Example B6: Aluminum + Chlorine Al Cl Mg2+ + Cl1- + Cl1- Æ MgCl2 Cl Cl Cl Al3+ + Cl1- + Cl1- + Cl1- Æ AlCl3 Challenge: What are some other ionic bonds that can be formed by the elements you see? Write the chemical formula for the compound and its name. Answers will vary. ANSWER KEY Section C: Covalent Bonds What is a covalent bond? Atoms share one or more electrons with each other to form the bond. Each atom is left with a complete outer shell. A covalent bond forms between two nonmetals. Example C1: Hydrogen + Hydrogen H H Example C2: 2 Hydrogen + Oxygen H H O H Example C3: Chlorine + Chlorine Cl Cl H 2O Example C4: Oxygen + Oxygen Cl O Cl2 O Example C5: Carbon + 2 Oxygen O O O2 Example C6: Carbon + 4 Hydrogen H O H O C C H H O C O H CH4 CO2 H C H H O H H H2 Cl H