Complex Formation and Precipitation
EXPERIMENT 4
TITLE
Complex Formation and Precipitation.
INTRODUCTION
Precipitation is the formation of a solid in a solution as the result of either a chemical reaction, or supersaturating a solution with a salt resulting in solid material collecting on the bottom of the beaker (Housecroft & Constable, 2006). When the solution has been supersaturated by a compound and no more material can be supported by the solution, it considered as precipitate. Commonly, the solid will fall out of the solute phase and sinks to the bottom part of the solution. However, the solid may float on top of the solution or suspended within the solution if the precipitate is less than the aqueous solution.
On the other hand, complex formation is the soluble compound that can increase the solubility of an insoluble salt form in aqueos solution (Housecroft & Constable, 2006). They are formed from a cation such as water or ammonia that has pair of electrons that become attracted to the positively charged cation. In terms of the solubility, the formation of a complex lowers the concentration of the cation in the solution.
In this experiment, there are 3 parts need to be done which is complex formation, weak acids and bases and precipitation reaction. During complex formation experiment, student needs to observe the different reaction occur when adding ammonia or sodium hydroxide in small quantity and in excess. At the second part, student needs to measure the pH of different solution by using universal indicator paper and determine whether each solution is acidic, basic or neutral. Lastly, the precipitation reaction is observed by using phosphates, chlorides and silver halides groups.
AIMS
The main objective of this experiment was to identify certain inorganic reaction types and the differences in solubility of silver halides. Thus, a series of inorganic reactions was carried out as an introduction to complex formation and precipitation. All the reaction in this experiment
TITLE
Complex Formation and Precipitation.
INTRODUCTION
Precipitation is the formation of a solid in a solution as the result of either a chemical reaction, or supersaturating a solution with a salt resulting in solid material collecting on the bottom of the beaker (Housecroft & Constable, 2006). When the solution has been supersaturated by a compound and no more material can be supported by the solution, it considered as precipitate. Commonly, the solid will fall out of the solute phase and sinks to the bottom part of the solution. However, the solid may float on top of the solution or suspended within the solution if the precipitate is less than the aqueous solution.
On the other hand, complex formation is the soluble compound that can increase the solubility of an insoluble salt form in aqueos solution (Housecroft & Constable, 2006). They are formed from a cation such as water or ammonia that has pair of electrons that become attracted to the positively charged cation. In terms of the solubility, the formation of a complex lowers the concentration of the cation in the solution.
In this experiment, there are 3 parts need to be done which is complex formation, weak acids and bases and precipitation reaction. During complex formation experiment, student needs to observe the different reaction occur when adding ammonia or sodium hydroxide in small quantity and in excess. At the second part, student needs to measure the pH of different solution by using universal indicator paper and determine whether each solution is acidic, basic or neutral. Lastly, the precipitation reaction is observed by using phosphates, chlorides and silver halides groups.
AIMS
The main objective of this experiment was to identify certain inorganic reaction types and the differences in solubility of silver halides. Thus, a series of inorganic reactions was carried out as an introduction to complex formation and precipitation. All the reaction in this experiment
References: Heitz., M(2005) General Chemistry: An Integrated Approach, Chapter 16: More Equilibria in Aqueous Solutions: Slightly Soluble Salts and Complex Ions, 4th Edition, Prentice Hall, Inc., State University of New York. pp. 715-718 Housecroft, C.E. & Constable, E.C. (2006), Introduction to spectroscopy, in Chemistry, 3rd Edition, Pearson Education, England. pp. 951-970 Silberberg, M.S. (2006), Chemistry: The Molecular Nature of Matter and Change, 4th Edition, Mc Graw Hill International Edition, New York, pp. 1013-1019.