Practice questions covering chain, position, and functional group isomerism to help you understand how molecular structures differ while sharing the same molecular formula.
CH₃CH₂CHO (propanal) and CH₃COCH₃ (acetone) have the same molecular formula (C₃H₆O) but different functional groups (aldehyde vs. ketone), indicating functional isomerism.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
In CH₃CH₂C≡N, the carbon in CH₂ has four single bonds, indicating sp³ hybridization.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
No reaction with Lassaigne’s test indicates no halogens. CH₃CH₂COCH₂CH₃ (pentan-3-one) is a ketone consistent with C₅H₁₀O.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
CH₂=CHCH(CH₃)CH₃ (3-methylbut-1-ene) is a chain isomer with a terminal double bond.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
Mass of C = (12/44) × 0.66 = 0.18 g. Percentage = (0.18/0.25) × 100 = 72%.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
Cl⁺ is electron-deficient due to its positive charge, making it an electrophile.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
CH₃CH₂OH (ethanol) and CH₃OCH₃ (dimethyl ether) have the same molecular formula (C₂H₆O) but different functional groups (alcohol vs. ether), indicating functional isomerism.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
C₄H₁₀ (butane) has two structural isomers: n-butane (CH₃CH₂CH₂CH₃) and isobutane (CH₃CH(CH₃)CH₃).
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
Chain isomerism involves different carbon skeletons. CH₃CH(CH₃)CH₃ (2-methylpropane) has the same molecular formula (C₄H₁₀) as n-butane but a branched structure.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
Mass of S = (32/233) × 0.466 = 0.064 g. Mass of C = (12/44) × 0.44 = 0.12 g. Ratio = 0.064/0.12 ≈ 8:15.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
In CH₃CH₂C≡CH (but-1-yne), there are 9 σ bonds: 5 C-H, 2 C-C, 2 from C≡C.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
Mass of H = (2/18) × 0.135 = 0.015 g. Percentage = (0.015/0.15) × 100 = 10%.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism
