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.
Match the LIST-I with LIST-II:
Choose the correct answer from the options given below :
The number of molecules/ions that show linear geometry among the following is _____. SO₂, BeCl₂, CO₂, N₃⁻, NO₂, F₂O, XeF₂, NO₂⁺, I₃⁻, O₃
List I (Spectral Lines of Hydrogen for transitions from) | List II (Wavelength (nm)) | ||
A. | n2 = 3 to n1 = 2 | I. | 410.2 |
B. | n2 = 4 to n1 = 2 | II. | 434.1 |
C. | n2 = 5 to n1 = 2 | III. | 656.3 |
D. | n2 = 6 to n1 = 2 | IV. | 486.1 |
The following diagram shown restriction sites in E. coli cloning vector pBR322. Find the role of ‘X’ and ‘Y’gens :