tailieunhanh - Chemistry part 29, Julia Burdge,2e (2009)

Tham khảo sách 'chemistry part 29, julia burdge,2e (2009)', khoa học tự nhiên, vật lý phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | adding AgCl to water and stirring Therefore the concentrations are Neither AgCl nor a saturated solution of AgCl is purple. The color has been used In the resulting saturated solution the concentrations of Ag and CI- are equal and the product of their concentrations 708 1 f After filtering off the solid AgCl we dissolve enough NaCl to make the concentration of Cl - M. Because the concentration of CI is now larger the product of Ag and Cl concentrations is no longer equal to 7 sp In any solution saturated with AgCl at 25 C. the product of Ag and Cl-J must equal the sp of AgCl. Therefore AgCl will precipitate until the product of ion concentrations is again X 10 I0. Note that this causes nearly all the dissolved AgCl to precipitate. With a Cl- concentration of M the highest possible concentration of Ag is X 10 10 M. therefore Ag X 10 10 M The amount of AgCl precipitated is exaggerated for emphasis. The actual amount of AgCl would be extremely small. What s the point When two salts contain the same ion the ion they both contain is called the common ion. The solubility of a slightly soluble salt such as AgCl can be decreased by the addition of a soluble salt with a common ion. In this example AgCl is precipitated by adding NaCl. AgCl could also be precipitated by adding a soluble salt containing the Ag ion such as AgNO3. 709 710 CHAPTER 17 Acid-Base Equilibria and Solubility Equilibria Sample Problem demonstrates the effect of pH on solubility. Think About It When a salt dissociates to give the conjugate base of a weak acid H ions in an acidic solution consume a product base of the dissolution. This drives the equilibrium to the right i more solid dissolves according to Le Chatelier s principle. Which of the following compounds will be more soluble in acidic solution than in water a CuS b AgCl c PbSO4 Strategy For each salt write the dissociation equilibrium equation and determine whether it produces an anion that will react with HT Only an .