List - IMolecule | List - IIBond enthalpy (kJ mol-1) |
---|---|
(A) HCl | (I) 435.8 |
(B) N2 | (II) 498 |
(C) H2 | (III) 946.0 |
(D) O2 | (IV) 431.0 |
Bond enthalpy is the energy required to break one mole of a particular bond in a gaseous substance.
A. HCl: The H-Cl bond enthalpy is approximately 431 kJ mol$^{-1}$ (slightly lower than HBr and higher than HF due to periodic trends down the halogen group). Thus, A-IV.
B. N$_2$: The N≡N triple bond is very strong, with a bond enthalpy of approximately 946 kJ mol$^{-1}$. Thus, B-III.
C. H$_2$: The H-H single bond has a bond enthalpy of approximately 436 kJ mol$^{-1}$. Thus, C-I.
D. O$_2$: The O=O double bond has a bond enthalpy of approximately 498 kJ mol$^{-1}$. Thus, D-II.
Therefore, the correct matching is A-IV, B-III, C-I, D-II.
List-I (Compound / Species) | List-II (Shape / Geometry) |
---|---|
(A) \(SF_4\) | (I) Tetrahedral |
(B) \(BrF_3\) | (II) Pyramidal |
(C) \(BrO_{3}^{-}\) | (III) See saw |
(D) \(NH^{+}_{4}\) | (IV) Bent T-shape |
List I | List II | ||
---|---|---|---|
A | Mesozoic Era | I | Lower invertebrates |
B | Proterozoic Era | II | Fish & Amphibia |
C | Cenozoic Era | III | Birds & Reptiles |
D | Paleozoic Era | IV | Mammals |