Determine the molecular geometry and molecular polarity for TeF5-1

Determine the molecular geometry and molecular polarity for TeF5-1 Determine the molecular geometry and molecular polarity for TeF5-1 Square Planar polar Trigonal bipyramidal nonpolar Octahedral nonpolar Octahedral ionic Seesaw ionic T-shaped ionic Square pyramidal polar Trigonal bipyramidal polar T-shaped nonpolar Trigonal bipyramidal ionic Square Planar nonpolar Seesaw polar T-shaped polar Square Planar ionic Square pyramidal nonpolar Seesaw nonpolar Octahedral polar Square pyramidal ionic ÂÂ

The Correct Answer and Explanation is :

For the molecule TeF5⁻ (tellurium pentafluoride anion), we need to determine its molecular geometry and polarity.

Molecular Geometry:
TeF5⁻ consists of six electron pairs around the central tellurium (Te) atom: five bonding pairs with fluorine atoms and one lone pair. The arrangement of these electron pairs is primarily dictated by the need to minimize repulsion, following VSEPR (Valence Shell Electron Pair Repulsion) theory.

In the case of TeF5⁻, the molecule adopts a square pyramidal geometry. This configuration has a square base formed by four fluorine atoms, with a fifth fluorine atom at the apex of the pyramid, and the lone pair occupies a position that effectively distorts the pyramid, enhancing the square pyramidal shape.

Molecular Polarity:
The polarity of a molecule is determined by both the geometry and the electronegativity differences between the bonded atoms. Fluorine is highly electronegative, more so than tellurium. This significant difference creates polar bonds between Te and each F atom. However, the asymmetry of the square pyramidal shape (due to the lone pair at the vertex opposite the apex fluorine) leads to a lack of cancellation of these dipole moments.

Thus, TeF5⁻ is a polar molecule because the dipoles do not cancel out. The presence of a lone pair and the arrangement of the fluorine atoms around the tellurium atom in a non-symmetrical geometry contribute to a net dipole moment pointing from the tellurium towards the apex fluorine.

Now, let’s generate an image representing the molecular structure of TeF5⁻ in a square pyramidal geometry to visually understand its shape.

Here’s the illustration of the TeF5⁻ molecule in a square pyramidal geometry. This visual should help clarify the arrangement of the atoms and the molecular geometry I described. You can see how the lone pair and the asymmetric placement of the fluorine atoms contribute to the molecule’s overall polarity.