Author: Dr. Vikas Jasrotia

Aldehydes and Ketones – Distinguish Tests Class 12 Aldehydes and Ketones Que. Give simple chemical tests to distinguish between the following pairs of compounds. (i) Propanal and propanone (ii) Acetophenone and benzophenone (iii) Phenol and benzoic acid (iv) Benzoic acid and ethyl benzene (v) Ethanal and propanal (vi) Benzaldehyde and acetophenone Answers: (i) Propanal and Propanone: These two are distinguished by the iodoform test. propanal does not give an iodoform test when it reacts with I2 in the presence of NaOH while propanone gives an iodoform test when reacts with I2 in the presence of NaOH. CH3COCH3 + NaOI → CH3COONa +…

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CBSE Sample Paper Class 11 – Chemistry (Term 2 Solution) CBSE Sample Paper Class 11 – Chemistry (Term 2 Solution) To get paper click     —-     CBSE Sample Paper Class 11 – Chemistry (Term 2) SECTION –A Ans 1. (i) Dispersion force (ii) Dipole-dipole interaction (iii) Hydrogen bond (iv) Dipole-induced dipole interaction Ans 2. We have to find Density of ammonia (NH3) T = 30 + 273 = 303K, P = 5 bar, Mass of NH3 = 17gmol-1 R = 0.083 barLK-1mol-1 d = PM/RT, d = (5 × 17)/0.083 × 303 = 3.379 gcm-3 Ans 3. (i) Arrange…

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CBSE Sample Paper Class 11 – Chemistry (Term 2) CBSE Sample Paper Class 11 To get answers click the link at the end MM: 70                                                                                                                      Time: 3h GENERAL INSTRUCTIONS: Read the following instructions carefully. (i) There are 24 questions in this question paper with internal choice. (ii) SECTION A – Q. No. 1 to 6 are very short answer questions carrying 2 marks each. (iii) SECTION B – Q. No. 7 to 22 are short answer questions carrying 3 marks each. (iv) SECTION C- Q. No. 23-24 are case study-based questions carrying 5 marks each. SECTION- A Que 1.…

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Mendeleev Periodic Table PDF Mendeleev’s Periodic Law (i) Properties of elements are periodic functions of their atomic weights. (ii) The elements are arranged in the increasing order of their atomic weights (iii) Similarities in physical and chemical properties” appear at regular intervals (iv) Mendeleev relied on the similarities in the empirical formulae and properties of the compounds formed by the elements. Characteristics of Mendeleev’s Periodic table. (i)  Nine vertical columns called groups.  These are designated as ), I, II, III, IV, V, VI, VII, and VIII.  Except for groups 0 and VIII, each group is further divided into two…

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Class 12 Chemistry Amines Practice Questions (Answers) Class 12 Chemistry Amines Practice Questions (Answers) To get Questions Click Class 12 Chemistry Amines Practice Questions Ans 1. Step 1. A mixture of two aromatic compounds (A) and (B) was separated by dissolving in chloroform followed by extraction with aqueous KOH solution. Compound + CHCl3 ——KOH (aq) → C6H5NH2 + C6H5OH A → C6H5NH2 (Aniline) B → C6H5OH (Phenol) Step 2. The organic layer containing compound (A), when heated with an alcoholic solution of KOH produced a compound (C) (C7H5N) associated with an unpleasant odour. C6H5NH2 + CHCl3 ——KOH (aq) → C6H5NC…

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Amines NEET Questions Amines NEET Questions Que 1. Which of the following are 10 amines? (a) Ethylenediamine (b) Dimethylamine (c) Trimethylamine (d) N-methyl aniline Ans 1. (a) Ethylene diamine (NH2 – CH2 – CH2 – NH2) Que 2. C3H9N represents (a) Primary amine (b) Secondary amine (c) Tertiary amine (d) All of these Ans 2. (d) All of these Explanation: CH3CH2CH2 – NH2 → 10 CH3CH2NHCH2 → 20 CH3N(CH3)2 → 30 Que 3. In the nitration of benzene using a mixture of Conc. H2SO4 and conc. HNO3 the species which initiates the reaction is: (a) NO2 (b) NO+ (c) NO2+…

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Amines Important Questions Class 12 – Chemistry Amines Important Questions Que 1. Why do amines act as Lewis Base? Ans 1. Amines have an unshared pair of electrons on nitrogen atoms due to which they behave as lewis base. Que 2. Which diazonium salt is stable at room temperature? Ans 2. Benzene diazonium  floro borate(C6H5N2 F). Que 3. What is diazotization? Write an example. Ans 3. The conversion of primary aromatic amines into diazonium salts is known as diazotization. Que 4. Which one is more basic  CH3NH2  or (CH3)3N in the gaseous phase and why? Ans 4. (CH3)3N is more basic because the…

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Give Reason for the Following Give Reason for the Following Que. (i) (a) Aldehydes are more reactive than ketone towards nucleophiles. (b) The boiling point of aldehydes and ketones is lower than that of the corresponding acid. (c) The aldehydes and ketones undergo a number of addition reactions. (ii) Give chemical tests to distinguish between: (a)Acetaldehydes and benzaldehyde (b)Propanone and propanal. Ans.  (i) (a) This is due to steric and electronic reasons, sterically the presence of two relatively large substituents in ketones hinders the approach of a nucleophile to carbonyl carbon than an aldehyde having only one such substituent. Electronically…

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MCQ Questions for Class 12 Chemistry Chapter 13 Amines with Answers MCQ Questions for Class 12 Chemistry with Answers Que 1. Out of the following compounds, which is the most basic in aqueous solution? (a) CH3NH2 (b) (CH3)2NH (c) (CH3)3N (d) C6H5NH2 Ans 1. (b) Explanation: Basicity is the ability of the atom to donate its lone pair of electrons. In aniline nitrogen is directly attached with the benzene ring which leads to the delocalization of lone pair of electrons of nitrogen atom in the benzene ring. This leads to the less availability of the electron for donation. In case…

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Carbon And Its Compounds Class 10 Questions with Answers PDF Carbon And Its Compounds Class 10 Questions with Answers PDF Que 1. Covalent compounds have low melting and boiling point. Why? Ans 1. Covalent compounds have low melting and boiling points because the forces of attraction between molecules of covalent compounds are very weak. Que 2. What is the role of concentrated H2SO4in the esterification reaction? Ans 2. In an esterification reaction, a carboxylic acid reacts with alcohol to form ester and water in the presence of concentrated sulphuric acid. This reaction is reversible and this reverse reaction is called ester hydrolysis.…

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