PMC 101- Organic chemistry Questions and Answers 2023

PMC 101- Organic chemistry Questions and Answers 2023 When showing electron movement during reactions? The octet rule must be fulfilled and electrons move from the nucleophile to the electrophile Which of the following carboxylic acids or carboxylic acids derivatives is the most reactive to a nucleophilic attack at the carbonyl carbon? Methanoyl chloride Which of the following statements is false regarding the chemistry of acyl phosphates? Acetyl-CoA and acyl phosphates can undergo condensation in lipid biosynthesis Which of the following statements regarding single- and 2-phase pharmaceutical formulations is most accurate? Suspensions and emulsions are 2-phase systems NH3 forms which of the following shapes? Tetrahedral Which of the following compounds would be the least soluble in water during an extraction purification? Hexane A pharmaceutical scientist wishes to formulate a new drug as a film-coated tablet formulation that will rapidly release the drug in the stomach. Which of the following would be the most appropriate polymer to use in the film coat? Hydroxypropyl methylcellulose Polymers can be characterised by a variety of different methods. Which of the following statements regarding polymer characterisation is NOT correct? Gel electrophoresis only separates polymers according to their charge Which of these reagents is not directly involved in the oxidation of alcohols? P-Toluenesulfonyl chloride What is the product of this fisher esterification reaction? Cyclohexyl 2-methylpropanoate What mechanism is responsible for the formation of imines when a primary amine is reacted with an aldehyde or ketone? Nucleophilic addition Which one of the options listed below would you expect to be the product of the addition of Cl2 to 1,2-dimethylcyclopentene Trans 1,2-dichloro-1,2-dimethylcyclopentane Which of the following is false regarding the reaction equilibrium in the acid catalysed synthesis of an ester from a carboxylic acid and an alcohol The yield of ester is improved by an excess of water Radical addition reactions of alkenes are less common in the laboratory/industry than in biological systems. Radical intermediates formed during radical addition reactions are not easily quenched in a lab reaction so the reaction can be difficult to control Alkenes react with N-Bromosuccinimide (NBS) in aqueous acidified DMSO to form which one of the following products Bromohydrin Cellulose acetate phthalate (CAP) is a polymer commonly used in the film coating of tablets. The polymer has weakly acidic functional groups of pka 4.66. If a CAP coated tablet is administered to a patient, at what site in the gastro-intestinal tract is the film coat likely to dissolve Small intestines What is the IUPAC name for (CH3)3CCH(OH)CH2CH(OH)CH2CH(CH3)2 2,2,7-Trimethyl-3,5-octanediol Which is the correct order of increasing acidity for these four compounds? (CH3)3COH CH3OH CF3CH2OH p-Methylphenol WHich of the following is NOT a recognized advantage of tablet coating Tablet coating can reduce the cost of manufacture A dibromophosphite is a reaction intermediate when converting an alcohol An alkyl bromide Which reagent is used to yield an aldehyde from a primary alcohol Dress-Martin periodinane Which of the following statements is false regarding nucleophilic acyl substitution reactions? In these reactions, the elimination of the leaving group is the second and rate limiting step What is the correct name for the following compound? 4,4-dimethyl-2-cyclohexenol Maleic acid is an intermediate in the tricarboxylic acid (TCA) cycle. What is its IUPAC name? Cis-butenedioic acid How would propanoic acid be different from propanol? Higher boiling point and higher solubility in water Choose the correct name for the following structure 3,4-diethylheptan-2-one The schematic diagram below represents a polymer: Alternating Copolymer Carbon dioxide forms which of the following shapes? Linear Which of the following statements is correct when the PH is two units more than the pKa value of a weakly basic drug Approximately 1% of the weakly basic drug molecules will be will ionised Which of these is not a method for preparing ketones? Oxidation of primary alcohols According solely to pH-partition theory, which of the following drugs is likely to have the LOWEST absorption from the stomach Propranolol ( a weakly basic drug, pKa 9.4) Alcohols and phenols have higher boiling points than might be expected due Hydrogen bonding WHat reagent is used in the named Wolff-Kishinev reaction to convert a carbonyl to an alkene? Hydrazine