Lesson 6 - Writing Chemical Formula of Ionic and Covalent Compounds PDF

Writing Chemical Formula of Compounds -Ionic -Covalent Prepared by: Abegail B. Palcongan Learning Targets At the end of the lesson you are able to: Write chemical formula of ionic and covalent compounds. REVIEW: Determine the number of valence electrons a...

Writing Chemical Formula of Compounds -Ionic -Covalent Prepared by: Abegail B. Palcongan Learning Targets At the end of the lesson you are able to: Write chemical formula of ionic and covalent compounds. REVIEW: Determine the number of valence electrons and draw the LEDS of the following elements: 1.Li 2.Ca 3.Al 4.O 5.S 6.P Determine the Charge of the ff. 1. Li elements. 2. Ca 3. Al 4. O 5. S 6. P  Ionic Compounds Metal + Nonmetal (Binary Compounds) Metal + Polyatomic anion Polyatomic cation + non-metal anion Polyatomic cation + Polyatomic anion Examples of metal ions: (Choose from the example in Review) Examples of non-metal anions: (Choose from the example in Review) **The non-metal ions are usually named by the element name and changing the ending with –ide. Example: oxygen-oxide; sulfur-sulfide; phosphorus-phosphide Transition Metal Ions Polyatomic Ions  Writing Chemical Formula: Ionic Compounds 1. The cation is written first, followed by the monatomic or polyatomic anion. 2. The subscripts in the formula must produce an electrically neutral formula unit. (That is, the total amount of positive charge must equal the total amount of negative charge.) 3. The subscripts should be the smallest set of whole numbers possible. 4. If there is only one of a polyatomic ion in the formula, do not place parentheses around it; e.g., NaNO3, not Na(NO3). If there is more than one of a polyatomic ion in the formula, put the ion in parentheses, and place the subscript after the parentheses; e.g., Ca(OH)2, Ba3(PO4)2, Writing Chemical Formula Examples: a. Ammonium Thiosulfate b. Ammonium Oxide c. Calcium Oxide d. Calcium Sulfate e. Sodium oxide f. Calcium Chloride Writing Chemical Formula: Formative Assessment 1 1. Magnesium nitrate 2. Magnesium Oxide 3. Iron (III) sulfide/ Ferric sulfide Writing Chemical Formula: Formative Assessment 1 4. Calcium carbide 5. Mercuric Cyanide 6.Calcium Hydroxide 7. Sodium Hydroxide  Covalent Compounds -non-metals sharing electrons Examples: 1. chlorine trifluoride 2. phosphorus pentachloride 3. sulfur dioxide 4. dinitrogen pentoxide **Chemical formula of covalent compounds are also known as molecular compounds. Writing Chemical Formula of covalent compounds **Typically, a molecular formula begins with the nonmetal that is closest to the lower left corner of the periodic table except that hydrogen is almost never written first (H2O is the prominent exception). Then the other nonmetal symbols are listed. 1. Write the symbol of the first element listed, followed by the second element. 2. If there are prefix such as mono, di, or tri, place them as subscripts. Writing Chemical Formula of covalent compounds Prefixes and corresponding numbers: Mono=1; di=2; tri=3; tetra=4; penta=5; hexa=6; hepta=7; octa=8; nona=9, deca=10 Writing Chemical Formula of covalent compounds Examples: 1. chlorine trifluoride 2. phosphorus pentachloride 3. sulfur dioxide 4. dinitrogen pentoxide Formative Assessment 2: Writing Chemical Formula of covalent compounds 1. nitrogen dioxide 2. dioxygen difluoride 3. sulfur hexafluoride 4. selenium monoxide  References John McMurry and Robert C. Fay, Chemistry, 4th ed. Upper Saddle River, NJ: Pearson/Prentice Hall, 2004, p. 56-63. George E. Shankle & Harold W. Peterson, Laboratory Manual for Chemistry 1411. University publication at Angelo State University, San Angelo, TX 76909, p. 27-31. Formulas and Nomenclature of Ionic and Covalent Compounds https://www.angelo.edu/faculty/kboudrea/general/formulas_ nomenclature/Formulas_Nomenclature.htm Check if we attained the target At the end of the lesson you are able to: Write chemical formula of ionic and covalent compounds. SELF-EVALUATION LINK: https://forms.gle/L4A5cFAzQLoWsSS38