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The p-Block Elements — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe p-Block Elements2 Marks
Question
Explain the following facts giving appropriate reason in each case:
  1. $NF_3$ is an exothermic compound where as $NCl_3$ is not.
  2. All the bonds in $SF_4$ are not equivalent.
✓

Answer

  1. Because bond energy of $F_2$ is lower than that of $Cl_2$ and therefore F forms stronger bond with $N$ with the release of energy.
  2. $SF_4$ has trigonal bipyramidal structure with one $l.p.$ Due to $l.p-b.p$ repulsion two axial $S-F$ bonds are longer than two $S-F$ equatorial bonds.

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