why does the addition of hydrochloric acid in experiment 2 cause the solubility
ID: 697698 • Letter: W
Question
why does the addition of hydrochloric acid in experiment 2 cause the solubility of the bicyclic diacid in water to decrease ?
these two phtos are related to experiment 2
290 Organic Experiments 2. Brown Hydrogenation NaBH-HCI PiCI COOH COOH COOH COOH cis-Norbornene-5,6-endo- dicarboxylic acid mp 180-190°C, dec MW 182.17 cis-Norbornane-5,6-endo. dicarboxylic acid mp 170-175°C, dec MW 184.19 is reduced with borohydride to IN THIS EXPERIMENT platinum chloride lic platinum that is deposited on charcoal. An aqueous solution of an alkene carboxylic acid and a borohydride solution is added to the sealed fl hydrogen gas is rapidly absorbed while swirling the solution. The aqueçous solution is extracted with ether and in the usual way the ether is washed dried, and evaporated. The solid product is recrystallized from aqueous hydrochloric acid metal. ask. T See Fig. 25.4 for a quantitative hydrogenation apparatus. However, in this experiment we will measure the uptake of hydrogen in a semiquantitative manner. Leveling bulb Hydrogen in To aspirator FIG. 25.4 Apparatus for quantitative hydrogenation. Air in the apparatus is removed with an aspirator, and hydrogen is admitted and brought to atmospheric pressure by raising or lowering the leveling bulb. The stirrer is started, and the amount of hydrogen taken up is measured in the gas burette after again bringing the pressure inside to that of the atmosphere. Sample and catalyst Mercury Stirrer 1. H. C. Brown and C. A. Brown, J. Am. Chem. Soc., 84, 1495 (1962)Explanation / Answer
Both HCl and norbornene dicarboxylic acids have common ion H+, due to common ion effect the equilibrium shifts reactant side (left side), hence the solubility of norbornene-endo-dicarboxylic acid will decrease in water. Just how this technique is industrially using to precipitate table salt (NaCl - Sodium Chloride) by adding HCl to the solution of NaCl.
-COOH (aq) + H2O (l) <==> -COO- (aq) + H3O+(aq)
This can also be explained by Lechatlier's principle. If we perturb the equilibrium by changing concentration, pressure,temperatute then equilibrium is shifted to counteract to nullify the effect. Actually the solubility of diacid is due to the solvation of carboxylate anion whenever H+ added this suppress the solvation.
Thank You So Much! Please Rate this answer as you wish.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.