ANCH WEEK 9: Solving Equilibrium Problems for Complex System

• Aqueous Solutions


  often species that interact with one another and water to yield two or more simultaneous equilibria
• Five independent algebraic equations


  is needed to calculate the solubility of a chemical to simultaneously give five concentrations
• Mass-Balance Equation


  relate to the equilibrium concentrations of various species in a solution to one another and to analytical concentrations of the various solutes
• Charge-Balance Equations


  Electrolyte are electrically neutral even though they contain up to several moles per liter of charged ions
• Solutions are neutral

  because the molar concentration of positive charge in an electrolyte solution always equals the molar concentration of negative charge
• Solutions containing electrolytes, may be written as:


  no. moles/L positive charge = no. moles/ L negative charge
• Charge-Balance Equations


  represents the charge-balance condition

  must be expressed in terms of the molar concentration of the species that carry a charge in the solution