Chemistry Lecture 7: Molar Mass, Empirical Formulas, and Chemical Equations, Lecture notes of Organic Chemistry

Download Chemistry Lecture 7: Molar Mass, Empirical Formulas, and Chemical Equations and more Lecture notes Organic Chemistry in PDF only on Docsity! Chem 111 L t ec ure 7 UMass Amherst Biochemistry Teaching Initiative... Homework • Continue Reading Chapter 3 OWL li h k• on ne omewor . 2... Let’s Practice Calculate the percentage of nitrogen (by mass) in Ca(NO3)2. 5... Let’s Practice Calculate the number of C atoms in 0.350 mol of C6H12O6 6... Let’s Practice Anti-freeze, ethylene glycol, is composed of 38.7% carbon, 9.7% hydrogen and 51.6% oxygen by mass. Its molar mass is 62.1 g/mol. What is its molecular formula? 7... Combustion reactions Most reaction involve combining O2 from air with a reactant. When hydrocarbons are combusted they form CO2 + H2O. Suppose we combust (or burn) methanol: CH3OH(l) + O2 (g) CO2(g) + H2O(l) 1 Balance Carbons:. CH3OH(l) + O2 (g) CO2(g) + H2O(l) 2 Balance Hydrogens:. CH3OH(l) + O2 (g) CO2(g) + 2H2O(l) 3. Balance Oxygens: CH3OH(l) + 3/2 O2 (g) CO2(g) + 2H2O(l) 4. Remove Fractional Coefficients 10 2 CH3OH(l) + 3O2 (g) 2 CO2(g) + 4 H2O(l) ... Chemical Equilibrium Chemical Equilibrium – occurs when opposing reactions are proceeding at the same rate. N O ( ) 2NO ( )2 4 g 2 g 2NO2 (g) N2O4 (g) 11... Solutions Solution – is a homogeneous mixture of two or more substances. Solvent - is the component that is present in greater quantity. Solute - is the component that is present in lesser quantity. It is said to be dissolved in the solvent. Aqueous Solutions – Solutions where water is the solvent. 12... Ionic Compounds in Water 15 CH3CO2H (aq) ⇋ CH3CO2 - (aq) + H+ (aq) ... Solubility SOLUBLE COMPOUNDS Almost all salts of Na*, K”, NH,” Almost all salts of CO, Br, 1 Salts containing F~ Salts of sulfate, S0,?— EXCEPTIONS INSOLUBLE COMPOUNDS EXCEPTIONS a Fig. 3-10, p. 126 blolelelée le OF |...[4]4)> 16