TeF5- Lewis structure

TeF₅^– has one tellurium atom and five fluorine atoms.

In TeF₅^– Lewis structure, there are five single bonds around the tellurium atom, with five fluorine atoms attached to it. Each fluorine atom has three lone pairs, and the tellurium atom has one lone pair.

Also, there is a negative (-1) charge on the tellurium atom.

Alternative method: Lewis structure of TeF₅^–

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, tellurium lies in group 16, and fluorine lies in group 17.

Hence, tellurium has six valence electrons and fluorine has seven valence electrons.

Since TeF₅^– has one tellurium atom and five fluorine atoms, so…

Valence electrons of one tellurium atom = 6 × 1 = 6
Valence electrons of five fluorine atoms = 7 × 5 = 35

Now the TeF₅^– has a negative (-1) charge, so we have to add one more electron.

So the total valence electrons = 6 + 35 + 1 = 42

Learn how to find: Tellurium valence electrons and Fluorine valence electrons

• Second, find the total electron pairs

We have a total of 42 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 42 ÷ 2 = 21

• Third, determine the central atom

We have to place the least electronegative atom at the center.

Since tellurium is less electronegative than fluorine, assume that the central atom is tellurium.

Therefore, place tellurium in the center and fluorines on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 21 electron pairs. And five Te — F bonds are already marked. So we have to only mark the remaining sixteen electron pairs as lone pairs on the sketch.

Also remember that tellurium is a period 5 element, so it can keep more than 8 electrons in its last shell. And fluorine is a period 2 element, so it can not keep more than 8 electrons in its last shell.

Always start to mark the lone pairs from outside atoms. Here, the outside atoms are fluorines.

So for each fluorine, there are three lone pairs, and for tellurium, there is one lone pair.

Mark the lone pairs on the sketch as follows:

Formal charge

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For tellurium atom, formal charge = 6 – 2 – ½ (10) = -1

For each fluorine atom, formal charge = 7 – 6 – ½ (2) = 0

Here, the tellurium atom has a charge, so mark it on the sketch as follows:

Final structure

The final structure of TeF₅^– consists of a central tellurium atom connected to five fluorine atoms through single covalent bonds. In this configuration, the tellurium atom utilizes an expanded valence shell to accommodate twelve electrons, which includes five bonding pairs and one lone pair. Within this layout, each of the five fluorine atoms fulfills the octet rule by maintaining three lone pairs alongside its single shared bond. This arrangement represents the most stable state for the ion because it results in a formal charge of -1 on the central tellurium atom, while all five fluorine atoms carry a formal charge of zero. Accordingly, this specific electronic distribution serves as the definitive and most accurate Lewis representation of the TeF₅^– ion.

To properly represent this as a polyatomic ion, the entire Lewis structure is enclosed within square brackets. The overall charge of 1- is then written as a superscript outside the brackets at the top right, indicating that the structure possesses one additional electron beyond the valence count of the neutral atoms.

Next: SeCl₆ Lewis structure

External links

• https://homework.study.com/explanation/draw-the-lewis-structure-for-tef5-and-provide-the-following-information-a-total-number-of-valence-electrons-b-number-of-nonbonding-electron-pairs-c-electron-geometry-d-molecular-geometry-e-polarity.html
• https://www.chegg.com/homework-help/structure-tef5-draw-complete-lewis-structure-tef5-explain-di-chapter-20-problem-55ae-solution-9780547054056-exc