Oxidation with tollens reagent provides a distinct

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Oxidation with Tollens reagent provides a distinct color change, because the Ag+ reagent isreduced to silver metal (Ag), which precipitates out of solution.Aldehydes give a positive Tollens
test; that is, they react with Ag+ to form RCOOH and Ag. When the reaction is carried out in aglass flask, asilver mirror is formed on its walls. Other functional groups give a negative Tollens test, becauseno silver mirror forms (Smith, 2011). The reaction is shown below (Adapted from Smith, 2011)Another focus of this part was the carbohydrates—its functions and some of its examples.Now look around you. Have you ever found a carton of milk or a bowl of rice? What do you thinkis highly present at those? What is present is carbohydrate—Carbohydrates, the largest group ofbiomolecules in nature, comprising ~50% of the earth’s biomass (Smith, 2011). Carbohydrates,commonly referred to as sugars and starches, are polyhydroxy aldehydes and ketones, orcompounds that can be hydrolyzed to them. The cellulose in plant stems and tree trunks and thechitin in the exoskeletons of arthropods and mollusks are just examples of complex carbohydrates.Carbohydrates serve as storehouses of chemical energy. They are synthesized in green plants andalgae by photosynthesis, a process that uses the energy from the sun to convert carbon dioxide andwater into glucose and oxygen. This energy is released when glucose is metabolized.The simplest carbohydrates are called monosaccharides or simple sugars which have threeto seven carbon atoms in a chain, with a carbonyl group at either the terminal carbon (C1) or thecarbon adjacent to it (C2). Monosaccharides with an aldehyde carbonyl group at C1 are calledaldoses, meanwhile monosaccharides with a ketone carbonyl group at C2 are called ketoses. Avisual representation is shown below:In addition, carbohydrates are also classified by the number of carbon atoms in themolecule (triose, tetrose, pentose, hexose, and so on). Carbohydrates displayed below are d-Glyceraldehyde and dihydroxyacetone which have the same molecular formula, and are referred toas constitutional isomers.
4.Organic compounds have one property in addition to their solubility, melting point, andboiling point: acidity. The pH scale, which is used to specify the acidity or basicity of an aqueoussolution, is used to define acidity. In terms of acidity, carboxylic acids are the most acidic of theorganic compounds. Carboxylic acid is a carboxyl group (COOH) attached to an alkyl or arylgroup organic compound. They produce carboxylate ions when they react with metals and alkalis.These carboxylic acid reactions demonstrate their acidic nature. Compounds with a -OH groupattached to a hydrocarbon, such as alcohols and phenol, on the other hand, are very weak acids(Morsch, 2020). For phenol, the key factor that affects its acidity is its conjugate base which is thephenoxide. The negative charge, however, delocalizes into the benzene ring to a lesser extent viaresonance than the benzene ring donates electrons to the O ion via induction. Overall, the negativecharge on O is intensified, and the conjugate base of phenol is less stable. As a result, the strongerthe acid, the more stable the conjugate base of the acid.

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Term
Fall
Professor
GabrielCuevas
Tags
Carboxylic acid, Functional group, OH group

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