Potassium Permanganate Lab Report
Primary alcohols undergo oxidation to form carboxylic acids in two stages, it forms an aldehyde and then to the acid. In this experiment, we are used to prepare benzoic acid from benzene. Potassium permanganate is used this operation as an oxidizing reagent, it is used to oxidize the benzoic acid as well as acting as a catalyst for the reaction. Potassium permanganate (KMnO4) is a very strong oxidant which is able to react with many functional groups, such as secondary alcohols, 1,2-diols, aldehydes, alkenes, oximes, sulfides and thiols.
It is heated under a reflux, this (heating in a flask with a condenser placed vertically in it) prevents any aldehyde formed in the reaction escape and allow it to have time to be oxidized to carboxylic acid. …show more content…
However, it is very likely that at least some of the benzoic acid was lost during that kind of processes, because the product had to be transferred between several containers, and different filters were used. Some of the benzoic acid is lost when we filtered out the soluble impurities, because the acid is soluble as it donates its proton. Even though, the addition of HCl shifted the equilibrium towards the side where the benzoic acid is not dissociated, we could not keep all the acid. The mixture was then filtered through a pre-heated Buchner funnel. Any insoluble impurities remained on the paper will be the residue. Most of the benzoic acid crystallize when it is cooled using ice. Impurities that are soluble were left in solution. The mixture was again filtered at the pump, this time while cold. The residue on the filter is the purified benzoic acid. This residue was washed by running a little deionized water over it in order to remove the salt solution. Running the pump for a short while after filtration encourages drying of the
It is heated under a reflux, this (heating in a flask with a condenser placed vertically in it) prevents any aldehyde formed in the reaction escape and allow it to have time to be oxidized to carboxylic acid. …show more content…
However, it is very likely that at least some of the benzoic acid was lost during that kind of processes, because the product had to be transferred between several containers, and different filters were used. Some of the benzoic acid is lost when we filtered out the soluble impurities, because the acid is soluble as it donates its proton. Even though, the addition of HCl shifted the equilibrium towards the side where the benzoic acid is not dissociated, we could not keep all the acid. The mixture was then filtered through a pre-heated Buchner funnel. Any insoluble impurities remained on the paper will be the residue. Most of the benzoic acid crystallize when it is cooled using ice. Impurities that are soluble were left in solution. The mixture was again filtered at the pump, this time while cold. The residue on the filter is the purified benzoic acid. This residue was washed by running a little deionized water over it in order to remove the salt solution. Running the pump for a short while after filtration encourages drying of the