0
During non-aqueous titration of amine salts, the halide ions, namely: chloride, bromide and iodide are very weakly basic in character so much so that they cannot react quantitatively with acetous perchloric acid. In order to overcome this problem, mercuric acetate is usually added (it remains undissociated in acetic acid solution) to a halide salt thereby causing the replacement of halide ion by an equivalent amount of acetate ion, which serves as a strong base in acetic acid as shown below: 2R.NH2.HCl ↔ 2RNH3 + + 2Cl - (CH3COO) 2 Hg + 2Cl- → HgCl2 + 2CH3COO- undissociated 2CH3COOH2+ + 2CH3COO- ↔ 4 CH3 COOH
Still curious? Ask our experts.
Chat with our AI personalities
Blake
Rafa
LaoMercuric acetate is used in non-aqueous titrations because it is insoluble in non-aqueous solvents, allowing for a stable titrant solution. It also forms a complex with the analyte, which helps to enhance the sensitivity and selectivity of the titration. Additionally, mercuric acetate is a strong oxidizing agent, making it suitable for titrating compounds that are difficult to oxidize.
Add your answer:
Earn +20 pts
Why is mercuric acetate employed in non aqueous titrations and by what mechanism does it work?
Mercuric acetate is used in non-aqueous titrations because it is soluble in organic solvents. It functions as an oxidizing agent, converting the species being titrated into a form that can be easily detected by a color change or other indicator. This mechanism involves the transfer of electrons between the analyte and mercuric acetate, resulting in the formation of a colored complex that signals the end point of the titration.
Why is acetic acid used in the synthesis of phenylmercuric acetate by combining mercuric acetate with benzene?
Acetic acid is used to facilitate the reaction by providing the acetate ions needed to react with the mercuric ions in mercuric acetate. This reaction forms a mercury complex with the benzene molecule, which results in the formation of phenylmercuric acetate. This method allows for the selective functionalization of the benzene ring with the mercury atom.
What is the difference between aqueous and non aqueous titration?
Aqueous titration involves using a water-based solvent for both the titrant and the analyte, while non-aqueous titration involves using a solvent other than water. Aqueous titrations are more common and are used for analyzing compounds that are soluble in water, while non-aqueous titrations are used when water may interfere with the reaction or when the compounds are not soluble in water.
Titration involving bismuth sulfate and Titration involving mercuric nitrate?
Titration involving bismuth sulfate would typically be used to determine the concentration of a solution of a known or unknown substance that can react with bismuth ions. On the other hand, titration involving mercuric nitrate would be suited for determining the concentration of substances that can react with mercuric ions. Each titration method is specific to the ions involved and the chemical reactions occurring.
Why non-aqueous titration required?
Non-aqueous titration is required when the substances being titrated are insoluble or unstable in water or when the reaction involves non-aqueous solvents. This method is commonly used in organic chemistry to determine the concentration of acidic or basic substances in non-aqueous solvents like alcohols or acetone. Non-aqueous titration allows for accurate and precise determination of concentrations in these specific scenarios.
