Number Of Lone Pairs In Alcl4

The chemical formula AlCl4- represents a negatively charged ion called tetrachloroaluminate, which is formed when aluminum (Al) combines with four chlorine (Cl) atoms.

In this ion, the aluminum atom has a formal charge of +3 and each chlorine atom has a formal charge of -1. Therefore, the total negative charge of the ion is 4(-1) = -4.

To determine the number of lone pairs in the tetrachloroaluminate ion, we need to first determine its molecular geometry. The VSEPR theory predicts that the geometry around the central aluminum atom will be tetrahedral, with the four chlorine atoms arranged symmetrically around it.

In a tetrahedral molecular geometry, the central atom has four electron pairs arranged around it, with each pair occupying one of the four corners of a regular tetrahedron. Two of these electron pairs are bond pairs, representing the covalent bonds between the aluminum atom and the chlorine atoms. The other two electron pairs are lone pairs, which are not involved in bonding.

Therefore, the tetrachloroaluminate ion contains two lone pairs of electrons around the aluminum atom.