1. Using the values of DHf° and S° provided, calculate the quantities listed below for the following phase change in ethanol, CH3CH2OH. CH3CH2OH(l) ⇄ CH3CH2OH(g) DHf° [CH3CH2OH(l)] = -277.69 kJ/mol DHf° [CH3CH2OH(g)] = -235.10 kJ/mol S°[CH3CH2OH(l)] = 160.7 J/mol·K S°[CH3CH2OH(g)] = 282.7 J/mol·K The sign of DS°total will inform us as to whether […]
1. Consider two identical four-atom solids, one having 4 quanta of energy and the other having 10. (a) What observable property differs between these two solids? The two solids have different amounts of thermal energy and will be at different temperatures. The four-atom solid with 10 energy quanta is at a higher temperature than the […]
1. Write the equilibrium-constant expression, in terms of concentrations, for each of the following reactions. (a) TiCl3(s) W TiCl(s) + Cl2(g) Kc = [Cl2] (b) CuCl42-(aq) W Cu2+(aq) + 4 Cl – (aq) Kc = ([Cu2+ ][Cl – ]4)/[CuCl42- ] (c) CO(g) + H2O(g) W CO2(g) + H2(g) Kc = ([CO2][H2])/([CO][H2O]) (d) 4 H3O+(aq) + […]
1. Hydrogen peroxide (H2O2) is used in concentrated solution in rocket fuels and dilute solution as hair bleach. An aqueous solution of H2O2 is 30.0% by mass and has a density of 1.11 g/mL. Calculate the following quantities for this solution: (a) molality of H2O2, (b) mole fraction of H2O2, and (c) molarity of H2O2. […]
