GC1 Module 3 Chemical Nomenclature.pdf

General Chemistry 1 Module 3 Chemical Nomenclature Prepared by: Kristel P. Mendoza, LPT, MAEd Subject Teacher Timeline: 1 kpmendo...

General Chemistry 1 Module 3 Chemical Nomenclature Prepared by: Kristel P. Mendoza, LPT, MAEd Subject Teacher Timeline: 1 kpmendoza2024  Introduction Chemical nomenclature is a systematic way of naming of compounds or chemicals. Naming of compounds and properly identifying them is essential especially to those students who plan to take allied health courses and biology or chemistry major in college. This programmed instruction is a step by step process that will help you learn how to name compounds or molecules. It also aims you to know how to properly write chemical formula as this is a prerequisite to the succeeding lessons such as writing chemical equations and balancing equations. Follow each of the instructions given and DO NOT SKIP anything from this Programmed Instruction. In this programmed instruction, you are expected to be actively involved in the learning process by filling in the blanks, tables or boxes that require your answers. Learning Goals: 1. Differentiate among atoms, molecules, ions and give examples (STEM_GC11AMIc-e-20); 2. Represent compounds using chemical formulas, structural formulas and models (STEM_GC11AMIc-e-21); 3. Name compounds given their formula and write formula given the name of the compound (STEM_GC11AMIc-e-23); 4. (LAB) Practice chemical nomenclature: writing the chemical formulas of ionic compounds; naming ionic compounds from formulas (STEM_GC11AMIc-e- 24). At the end of this programmed instruction, you will be tasked to summarize what you have learned using a guided concept map. You are also tasked to assess your performance based on the learning goals. Let us begin! The KWL chart Before we start, you need to have a self assessment of your knowledge about periodic table. Fill up the KWL chart below, list down what did you learn about chemical nomenclature. K-What do I know about What I want to Know What I did learn about chemical nomenclature? chemical nomenclature? chemical nomenclature? 2 kpmendoza2024  Great! Now, you have assessed your knowledge about chemical nomenclature. You may also access the ff link https://youtu.be/fHVyIBXlOrQ for a recorded video tutorial of the lesson Part A. Atoms, Molecules and Ions As previously discussed from Programmed Instruction 3, atoms are the basic unit of matter. Ions are charged particles namely cation and anion. When these atoms, cation and anion combine together, they form molecules. In other words, a molecule is a group of atoms and ions that are chemically bonded with a net charge of 0. For example, a water molecule (H2O) is composed of two hydrogen atoms and one oxygen atoms. Table salt or sodium chloride is composed of ions: sodium cation (Na+) and chloride anion (Cl-). Learning Goal 1. Differentiate among atoms, molecules, ions and give at least 5 examples for each. You may research the internet or use books and other references in providing examples. Description/Definition Examples Atoms Molecules Cations Anions 3 kpmendoza2024  There are different ways how these atom bond together. These are called chemical bonding. Chemical bonding is important for a certain molecule to form. Covalent Bonding- Sharing of electron between Non-metal + non-metal Ionic Bonding- Transfer of electron between a Metal + non-metal Metallic Bonding- formation of metal to metal bonds. Recall from Programmed instruction 4a the different elements that are metals and non-metals. Can you name 3 metals? _____________, _____________, and _____________. Can you name 3 nonmetals? _____________, _____________, and _____________. Now, in order for you to understand more about chemical bonding and naming, recall that the elements in the periodic table are arranged in groups or families and periods. The atoms in the periodic table can lose or gain electrons. Recall in PI 3, that a positively charged ion means that it LOSES electrons while a negatively charged ion means it has GAINED electrons. The metals are most likely to give electrons that is why they are positively charged while the nonmetals are most likely to gain electrons that is why they are negatively charged. The magnitude of their charges depends on the group or family they belong. 4 kpmendoza2024  Say for example, group 1 elements which are metals have a charge of 1+. Thus, hydrogen ion is written as H1+ or simply C. Group 2 elements such as Magnesium and Calcium can be written as Mg2+ and Ca2+ respectively. For non-metals, starting from group 7, the charge of the ion is 1-, group 6 2- and group 5 is 3-. Thus, Chlorine has a charge of 1- and can be written as Cl1- or simply Cl- ; Oxygen has a charge of 2- and written as O2- while Nitrogen has a charge of 3- can be written as N3-. Practice. Write the group number, symbol and the charge of the following atoms. Refer to your periodic table Atom Group Charge Symbol Sodium 1 1+ Na+ Barium Fluorine Phosphorus Sulfur Part B. Naming Ionic compounds 1. Metals + monatomic anions In ionic bonding, a metal is always written first before a nonmetal. Moreover, ionic bonding is the attraction of two opposite charges- the positively charged metal and a negatively charged non-metal. For example, let us combine Barium and sulfur. Ba2+ + S2- Now, take note of their charges. Do they have the same value? Yes. Both of them have a charged of 2+. Recall that a molecule has a zero net charge. Mathematically, when the charges are added the answer is 0. Thus, when Ba and S are combined, they will have a net charge of 0. The molecule that was formed BaS is the molecular formula. In naming ionic compounds, retain the name of the metal while change the suffix of the non-metal with –ide. Thus, the name of a molecular formula BaS is barium sulfide. In other words, 1 atom of barium can be combined with 1 atom of sulfur. Let us have another example. Let us try to combine sodium and and phosphorus. Na+ + P3- Notice their charges, are they the same? No. Sodium has a charge of +1 while phosphorus has a charge of 3-. Mathematically, if we add 1+ and 3-, we will get 2-. 5 kpmendoza2024  Now, how can we combine the atoms having a net charge of 0? To make the charges equal, we need 3 atoms of sodium. Na+ Na+ Na+ + P3- From the equation above, three sodium atoms are needed to be combined with phosphorus to create a molecule. To write it, place a number 3 as a subscript for Na. Na+ Na+ Na+ + P3- → Na3 P The molecule that was formed Na3 P is the molecular formula. Thus, the name of a molecular formula Na3 P is sodium phosphide. In other words, 3 atoms of sodium can be combined with 1 atom of phosphorus. A much simpler way of writing the chemical formula when there are unequal charges is by the crossing over method. Here, the value of the charge of one atom becomes the subscript of the other. For example, let us try to combine calcium and fluorine. Ca+2 + F- → Ca1 F2 → CaF2 By convention, the value 1 need not to be written because it is already given that there is one atom of that element. The molecule that was formed CaF2 is the molecular formula. Thus, the name of a molecular formula CaF2 is calcium fluoride. In other words, 1 atom of calcium can be combined with 2 atoms of fluorine. Learning Goal 2. Represent the following as chemical or molecular formula and name the molecule. Elements Cation Anion Molecular Name charge charge formula Sodium and chlorine Na+ Cl- NaCl Sodium chloride Magnesium and bromine Calcium and Oxygen Potassium and oxygen 6 kpmendoza2024  2. Metals + polyatomic anions Part B. Naming Ionic compounds using Old system and Stock System There are two ways of naming ionic compounds having inner transition metals as cations. These are the Old system and the Stock System. 1. Naming Using Old System In naming compounds using the old system, the old names of the cation metals are used. The table below lists some of the old names of the metals. Notice that the lower cation charge has a suffix- ous while the cation with a larger charge has a suffix –ic. 2. Naming using Stock system Table 1. List of some common polyatomic anions. Formula Name Formula Name OH- hydroxide NO3- nitrate O22- Peroxide NO2- nitrite CN- cyanide CH3COO- acetate N3- azide CrO42- chromate SO4 2- sulfate Cr2O7 dichromate 7 kpmendoza2024 SO32- sulfite MnO4 - permanganate HSO42- Hydrogen sulphate or bisulfate C2O4 2- oxalate HSO3- Hydrogen sulphite or bisulfite CNS- thiocyanate PO43- phosphate CO32- carbonate HPO43- Hydrogen phosphate HCO3- Hydrogen H2PO4 - Dihydrogen phosphate carbonate or bicarbonate 8 kpmendoza2024  Worksheet 1 NAMING OF COMPOUNDS Part A. Combine the anions above with the ff. common cations to form an ionic compound. Cation Symbol Anion Ionic compound Name formed (Formula) Potassium Calcium Sodium Magnesium Barium Part B. Name the following compounds having the following molecular formula Molecular formula Name KI MgCl2 NaCH3COO NaNO2 KNO3 9 kpmendoza2024  Part C. Write the molecular formula of the following compounds. Name Molecular formula Barium Chloride Lead Nitrate Sodium oxalate Copper(II) sulfate Ferric oxide Concept Mapping. Summarize the topics by providing the important concepts and relevant information. 10 kpmendoza2024  Now, you need to have an assessment of your performance. Rate how well you understood the topics and indicate in the remarks what difficulties did you encountered in the learning goals. 1 2 3 4 5 Remarks Learning Needs Fair Satisfactory Very Excellent improveme Satisfactory Goals nt 1 2 3 4 11 kpmendoza2024