Arsenic Pentachloride Lewis Structure

Arsenic pentachloride (AsCl5) is a covalent compound composed of one arsenic atom and five chlorine atoms. To draw its Lewis structure, we need to follow the octet rule, which states that atoms tend to gain, lose, or share electrons in order to achieve a stable electron configuration with eight valence electrons.

First, we determine the total number of valence electrons in AsCl5 by summing the valence electrons of each atom:

Arsenic (As): 5 valence electrons

Chlorine (Cl): 7 valence electrons x 5 = 35 valence electrons

Total: 5 + 35 = 40 valence electrons

Next, we place the arsenic atom in the center and surround it with the five chlorine atoms, each sharing one electron with the arsenic atom to form a single bond. This accounts for 10 valence electrons, leaving us with 30 more.

We then distribute the remaining electrons around the atoms to complete their octets. Each chlorine atom needs only one more electron to complete its octet, so we add one lone pair of electrons to each chlorine atom. This uses up 10 more electrons, leaving us with 20 more.

For arsenic, it already has a full first shell of 2 electrons, so it only needs 6 more electrons to complete its octet. We can achieve this by adding two more lone pairs of electrons to the arsenic atom, each shared with one of the chlorine atoms, forming double bonds between As and Cl atoms. This uses up 16 more electrons, leaving us with 4 remaining.

Finally, we add the last 4 electrons as lone pairs on the arsenic atom, completing the Lewis structure of AsCl5. The final structure has 5 single bonds between As and Cl atoms and two double bonds between As and Cl atoms, with each atom having a full octet of electrons.

The Lewis structure of arsenic pentachloride can be represented as follows:

Cl -- As -- Cl

with two double bonds between As and Cl atoms, and each atom having a full octet of electrons.