CHEM 111 1st Edition Lecture 3 Outline of Current LectureI. DefinitionsII. Molecular CompoundCurrent LectureMolecular Compound: When two or more elements form a molecule.- Molecular compounds typically form from nonmetals.Molecular Formula: A formula that gives the number of every type of atom in each molecule.- Subscripts used to express charge in molecule.Structural Formula: Shows which elements go into the structure of the molecule.Molecular Mass: The sum of the atomic masses of all the atoms, expressed in atomic mass units(u).- Ex: Calculate molecular mass of propane (C3H8)C=12.011 u 12.011x3=36.033H=1.008 u 1.008x8=8.064C3H8=44.097 uIonic Compounds: An ionic compound is composed of cations and anions forming a neutral species.- The formula of an ionic compound is an empirical formula that uses the smallest whole number as the subscript.- The relative numbers of ions in the empirical formula balances the charge to zero.- Positioning of an element on the periodic table can help determine the elements charge.(Ex: Oxygen2-, Sulfur2-)Polyatomic Ion: A group of atoms with a net charge that behaves as a single particle.- An example of a polyatomic ion is ammonium.- Barium and Nitrate - Ba2+(NO3-)2- Ammonium and Sulfate - (NH4+)2SO42-Formula Mass: The sum of the atomic masses of all the atoms in the empirical formula for an ionic compound.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Chemical Nomenclature: The organized system of naming compounds.- Metals have roman numerals in the elements name. FeCl3 is written as Iron (III) ChlorideAcids: An acid is a compound that produces hydrogen cations when dissolved in water.- Ex: HCl (Hydrochloric Acid) or H2SO4 (Sulfuric Acid)Hydrocarbons: Organic compounds that contain only the elements hydrogen and carbon.- Many of these compounds dissociate into smaller units.Electrolyte: A substance that forms ions in water solution.Chemical equation: A shorthand notation to describe a chemical reaction.- 2Mg+O2 -------------> 2MgO (Magnesium Oxide)Reactants of the chemical reaction are the substances that are consumed.Products of the chemical reaction are the substances that are formed.Balancing Equations:H2+Cl2 ---------> HCl (Unbalanced)Add coefficients so the # of atoms on each element is the same on both sides of the equationH2Cl2 -------> 2HCl (Balanced)C5H12+O2 -------> CO2+H2O (Unbalanced)C5H12+O2 -------> 5CO2 + 6H2O (Not completely balanced)C5H12 + 8O2 --------> 5CO2 + 6H2O