homework_sheet_3_complex_ions

4c

4e

Predict the solubility change (increase, decrease, or no change) of the following compounds. Explain your choice in details.   (a) Cu(OH)2 when adding HCl solution   (b) AgI when adding HCl solution   (c) PbCl2 when adding KCl solution

A solution contains CO32– at a concentration of 0.0023 M and Cl– at a concentration of 0.00076 M. If AgNO3(aq) is added drop by drop to the solution, which ion, CO32– or Cl–, will precipitate first? Give the minimum concentration of Ag+ needed to precipitate each of the

- 3 A chemistry graduate student is given 100. mL of a 0.30M diethylamine ((C,H,) NH) solution. Diethylamine is a weak base with K,= 1.3 × 10 °. what mass of (C,H5) NH,Br should the student dissolve in the (C,H,), NH solution to turn it into a buffer with pH = 10.94? 2 You may assume that the volume of the solution doesn't change when the (C,H,) NH,Br is dissolved in it. Be sure your answer has a unit symbol, and round 2 it to 2 significant digits.

The net ionic equation for the reaction occurring when a small amount of sodium hydroxide solution is added to a buffer solution containing NH4Cl and NH3 is correctly shown here: NaOH + NH --> NH3 + H₂O + Na+ True False

A chemistry graduate student is given 125. mL of a 0.30M dimethylamine ((CH,) NH) solution. Dimethylamine is a weak base with K,= 5.4 × 10 4 What mass of (CH,) NH,Cl should the student dissolve in the (CH,) NH solution to 2 2 turn it into a buffer with pH = 10.65? You may assume that the volume of the solution doesn't change when the (CH,) NH,Cl is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.