Both penicillin and cephalosporin are antibacterial drugs. On vigorous oxidation it gives ethanoic and propanoic acids. Benzoic acid does not show this test. (b) C6H5COCH3 < CH3COCH3 < CH2CHO As a result, nucleophilic addition reactions occur more readily in aldehydes than in ketones. (ii) Distinction between Benzaldehyde and Benzoic acid: Benzaldehyde has no alpha hydrogen atom. […], The key difference between cell and atom is that a cell is made of molecules whereas atoms make up molecules. On drastic oxidation with chromic acid, it gives a carboxylic acid ‘W having molecular formula C7H6O2. Answer: Question 32. (iii) Propanone to Propene (Comptt. Question 15. (iii) Phenol and Benzoic acid (All India 2009) (b) How are the following conversions carried out: Also find the composition of the vapour phase. Acetophenone-yellow precipitates of iodoform are formed. “Benzaldehyde.” National Center for Biotechnology Information. (a) Write the reactions involved in the following: (b) How will you bring about the following conversions? (ii) Cannizzaro’s reaction : Aldehydes, which do not have an oe-hydrogen atom undergo self oxidation and reduction on treatment with conc. All India 2017) All India 2012) IUPAC name : 2-methypropanal. PubChem Compound Database, U.S. National Library of Medicine, Available here. Aldehydes and ketones having at least one methyl group linked to the carbonyl carbon atom respond to iodoform test. Determine the molar mass of an ideal gas B if 0.622 g sample of gas B occupies a volume of 300 mL at 35 °C and 1.038 atm.? (iii) Since it undergoes Cannizzaro’s reaction, therefore CHO group is directly attached to the benzene ring. (b) How will you convert the following in not more than two steps: The molecular mass of the compound is 86. (b) An organic compound with molecular formula C9H10O forms 2, 4, – DNP derivative, reduces Tollens’ reagent and undergoes Cannizzaro’s reaction. But benzaldehyde (ii) Because of electron withdrawing nature of -NO2 group. (i) Benzoic acid and Ethyl benzoate, (ii) Benzaldehyde and Acetophenone. Question 91. (a) Describe the following giving chemical equations : Usually, a cell is on the […]. The key difference between benzaldehyde and benzophenone is that benzaldehyde is an aldehyde, whereas benzophenone is a ketone. Answer: Phenol and Benzoic acid 4. (a) Give chemical tests to distinguish between (Delhi 2013) to form a β-hydroxy aldehyde or β-hydroxy ketone respectively which gets dehydrated in the presence of acid upon heating to form α, β -unsaturated compound. The aldehyde will have 2 medium intensity bands just below 3000CM-1 due to aliphatic C-H stretch. (a) Although phenoxide ion has more number of resonating structures than carboxylate ion, carboxylic acid is a stronger acid than phenol. All India 2013) (i) p-Methylbenzaldehyde (ii) 4-Methylpent-3-en-2-one Answer: Ethanol: Ethanol does not form silver mirror with Tollen’s reagent. Question 25. Question 63. Further since oxidation of (C) with chromic acid produces the acid (B), therefore both the carboxylic acid (B) and the alcohol (C) must ’.contain the same number of carbon atoms. All Rights Reserved. Delhi 2012) (ii) Friedel-Crafts reaction: The introduction of alkyl or acetyl group in the presence of anhydrous almuninium chloride (AlCl3) as catalyst to ortho and para positions of an aromatic compound is called Friedel-Crafts reaction. If the solubility of H2S in water at STP is 0.195 m, calculate Henry's law constant. C6H5COCH3, CH3— CHO, CH3COCH3 It is due to weak molecular association in aldehydes and ketones arising out of the dipole- dipole interactions. Tollen’s reagent and undergoes Cannizzaro’s reaction. Overview and Key Difference 2. Answer: Question 51. (a) (ii) Propanal and Propanone : Propanal gives positive test with Fehling solution in which a red ppt. (a) Write the structures of A and B in the following reactions: Answer: Ethanal having one methyl group linked to the carbonyl carbon atom responds to this test. I appreciate it a ton!! (iii) The carboxylic carbon is less electrophilic than carbonyl carbon because of the possible resonance structure. (b) Write the product(s) in the following: (Comptt. (a) Mechanism of a nucleophilic attack on the carbonyl group Propan-2-one and pentan-3-one can be distinguished by Iodoform test. (i) Propanal and Propanone, (ii) Benzaldehyde and Acetophenone. (a) Write a suitable chemical equation to complete each of the following transformations : Answer: Answer: of iodoform. Answer: Question 6. (i) Cannizzaro reaction (ii) Decarboxylation (i) Ethanal and Propanal (ii) Phenol and Benzoic acid Question 78. (Comptt. It does not reduce Tollen’s reagent but forms an addition compound with sodium hydrogen sulphite and gives positive iodoform test. Answer: Question 20. However, benzaldehyde has one phenyl group attached to the carbonyl group because the other side of this carbonyl carbon has a hydrogen atom since it is an aldehyde. aqueous alkali giving product known as Aldol. Benzoic acid and Ethyl benzoate ... Benzaldehyde to Benzophenone 6. (i) LiAlH4 (Lithium Aluminium Hydride) B = 3-Hydroxybutanal (Aldol) It gets hydrolysed with dilute sulphuric acid and gives a carboxylic acid B and an alcohol C. Oxidation of C with chromic acid also produced B. Give the chemical equations involved. The carbonyl group of aldehyde and ketones is reduced to CH2 group on treatment with zinc amalgam and concentrated hydrochloric acid. (iii) On adding NaHCO,, benzoic acid produces brisk effervescence of C02 gas whereas ethylbenzoate does not. (ii) Aldol condensation: Those aldehydes and ketones with atleast one a-hydrogen atom condense together in presence of dil. “Benzaldehyde.” Wikipedia, Wikimedia Foundation, 15 June 2019, Available here. (Comptt. How could you distinguish between diphenyl ketone (also called benzophenone) and . Two moles of organic compound ‘A’ on treatment with a strong base gives two compounds ‘B’ and ‘C’. Example : (iii) The carboxylic carbon is less electrophilic than carbonyl carbon because of the possible resonance structure. Butanal gives silver mirror whereas Butan-2-one does not. (iii) Cross Aldol Condensation : When aldol condensation is carried out between two different aldehydes or ketones, it is called cross aldol condenstation. It does not reduce Tollen’s reagent but forms an addition compound with sodium hydrogen sulphite and gives positive iodoform test. Answer: Question 43. benzaldehyde using IR only? Answer: (b) (i) On heating with NaOH and I2, ethanal forms yellow ppt of CHI3 whereas propanal can not. Question 52. A = Ethanal 2. (i) Ethanol to 3-hydroxybutanal (ii) Benzaldehyde to Benzophenone (b) An organic compound A has the molecular formula C 8 H 16 O 2 . (ii) Acetophenone and Benzophenone: They can be distinguished by iodoform test which is given by only acetophenone with the formation of yellow ppt. 1-phenyl propan-1-one. Question 97. Hyphae represent the vegetative structure of fungi. Answer: Positive test Formation of a … Identify the compound and write all chemical equations for the reactions. Answer: Question 7. Iodoform test: Warm each organic compound with I2 and NaOH solution. The aldehyde carbonyl will also be higher ie close to 1700CM-1 with the ketone probably about 1650-1670. All India 2013) (i) Cross aldol condensation (ii) Decarboxylation IUPAC name : 2-methylcyclohexanone. Propanone on reacting with I2 and NaOH gives a yellow ppt of iodoform but propanal does not respond to this test. (b) Write the chemical equations to illustrate the following name reactions : (e) How can you distinguish between propanal and propanone? (c) CH3CHO < CH3CH2OH < CH3COOH. Some fungi are unicellular. Thanks!! CONTENTS 1. CH3CHO, CH3COOH, CH3CH2OH (All India 2016) (Comptt. By Iodoform test: Acetophenone being a methyl ketone on treatment with I2 and NaOH (NaOI) undergoes iodoform test to give yellow ppt. Answer: Question 104. Give a chemical test to distinguish between Benzoic acid and Phenol. Answer: (iii). (e) Propanal and Propanone: Propanal being an aldehyde gives positive test with Fehling solution in which a red brown ppt. (b) Give simple chemical test to distinguish between : (i) Electrophilic substitution in benzoic acid takes place at meta position. (i) Cannizzaro’s reaction reagent and undergoes Cannizzaro’s reaction. Write the structural formula of 1-phenylpentan- 1-one. (vi) Benzaldehyde and acetophenone can be distinguished by the following tests. (All India 2014) Delhi 2012) (iv) On oxidation it gives 1,2-benzenedicarboxylic acid, therefore it must be an ortho-substituted benzaldehyde, so the structure should be. Answer: Answer: (b) (i) Molecular formula of compound : C9H10O Add I2 and NaOH in both the solutions. A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? What is Tollen’s reagent? Give complete reaction in each case. Benzaldehyde does not respond to this test. (b) An organic compound (A) which has characteristic odour, on treatment with NaOH forms two compounds (B) and (C). (i) Benzoic acid from ethyl benzene, (ii) Benzaldehyde from toluene. (a) (i) Cannizzaro’s reaction: Aldehydes, which do not have an oc-hydrogen atom undergo self oxidation and reduction on treatment with cone, alkali and produce alcohol and carboxylic acid salt. By Iodoform test: (Comptt. Give a test to distinguish between propan-2-one and pentan-3-one. (d) Write the product in the following reaction: (b) How will you bring about the following converstions? (b) Arrange the following compounds in an increasing order of their property as indicated : Write the structure of 4-chloropentan-2-one. You can specify conditions of storing and accessing cookies in your browser. (b) (i) Aldehydes are more reactive than ketones due to the following two reasons : (ii) The benzene ring of benzoic acid undergoes electrophilic substitution reaction such as nitration, sulphonation etc. (a) Illustrate the following name reactions : (a) Write the product(s) in the following : (i) Ethanal and Propanal (ii) Benzoic acid and Phenol (Delhi 2013) All India 2015) 1. Rearrange the following compounds in the increasing order of their boiling points: (All India 2013)