18 public questions tagged with this topic.
2-Nitrophenol has intramolecular hydrogen bonding, reducing intermolecular forces and lowering its boiling point, while 4-nitrophenol has intermolecular hydrogen bonding, increasing its boiling point.
Ref: NCERT Class 12 Chemistry > Chapter 7: Alcohols, Phenols and Ethers > Topic: Physical Properties and Acidity of Alcohols and Phenols
Ethanol (CH₃CH₂OH) forms hydrogen bonds due to the -OH group, requiring more energy to break, whereas methoxymethane (CH₃OCH₃) lacks hydrogen bonding, leading to a lower boiling point.
Ref: NCERT Class 12 Chemistry > Chapter 7: Alcohols, Phenols and Ethers > Topic: Physical Properties and Acidity of Alcohols and Phenols
Methanol (CH₃OH) has a lower molecular weight (32 g/mol) than ethanol (CH₃CH₂OH, 46 g/mol), reducing van der Waals forces and thus lowering its boiling point.
Ref: NCERT Class 12 Chemistry > Chapter 7: Alcohols, Phenols and Ethers > Topic: Chemical Reactions of Alcohols - Dehydration Oxidation Esterification
Boiling points increase with molecular weight due to stronger London forces. The order is CH₃I (highest) > CH₃Br > CH₃Cl .
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Physical Properties - Boiling Point Dipole Moment Solubility
Boiling point increases with molecular weight due to stronger London forces. CH₃CH₂I has the highest molecular weight among the options.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Physical Properties - Boiling Point Dipole Moment Solubility
Boiling point decreases with lower molecular weight. CH₃CH₂F has the lowest molecular weight among the options.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Physical Properties - Boiling Point Dipole Moment Solubility
Δ Tb = 100.26 - 100 = 0.26 K . Δ Tb = Kb · m . 0.26 = 0.52 · m , m = 0.5 mol/kg . Cross-check: xsolute = (25 - 23.5/25) = 0.06 , but vapor pressure not needed here.
Ref: NCERT Class 12 Chemistry > Chapter 1: Solutions > Topic: Vapour Pressure and Raoult's Law - Ideal and Non-ideal Solutions
Straight-chain pentane has a higher boiling point than branched isomers like 2,2-dimethylpropane due to greater surface area and stronger van der Waals forces.
Ref: NCERT Class 11 Chemistry > Chapter 9: Hydrocarbons > Topic: Directive Influence and Carcinogenicity and Uses
For C₁₀H₂₂, 2,2,3,3-tetramethylhexane has four methyl branches, the most compact structure, lowering its boiling point the most.
Ref: NCERT Class 11 Chemistry > Chapter 9: Hydrocarbons > Topic: Alkynes - Preparation Properties and Acidic Character
Simple distillation is suitable for separating liquids with boiling point differences greater than 25–30°C.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Purification Methods - Crystallization Distillation Chromatography
Boiling point decreases with lower molecular weight in alkanes. CH₃CH₃ (ethane, MW 30) has the lowest MW among the options.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Fundamental Concepts - Reaction Mechanism - Fission and Reaction Intermediates
Boiling point increases with molecular weight in homologous series. CH₃CH₂CH₂CH₃ (butane, MW 58) has the highest MW among the options.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Classification and Nomenclature of Organic Compounds - IUPAC
