Question

sulfate ion so₄²⁻ will have which of the following? (hint: you will have to try out lewis structure drawing before you can come up with correct answer; and dont forget it has -2 charge 1) tetrahedral for both electron and molecular geometries 2) tetrahedral electron geometry and trigonal pyramid molecular geometry 3) trigonal pyramid for both electron and molecular geometry 4) tetrahedral for electron geometry and trigonal planar for molecular geometry

Explanation:

Step1: Determine the central atom

Sulfur (S) is the central atom in $[SO_{4}]^{2 -}$.

Step2: Calculate the number of valence - electrons

S has 6 valence electrons, each O has 6 valence electrons, and there is a - 2 charge. So the total number of valence electrons is $6 + 4\times6+2=32$.

Step3: Draw the Lewis structure

Connect the S atom to 4 O atoms with single bonds first. Then distribute the remaining electrons to satisfy the octet rule for each atom. In the Lewis structure of $[SO_{4}]^{2 -}$, the S atom has 4 bonding pairs and 0 lone pairs.

Step4: Determine electron - geometry and molecular - geometry

According to the VSEPR (Valence - Shell Electron - Pair Repulsion) theory, when the central atom has 4 bonding pairs and 0 lone pairs, both the electron - geometry and the molecular - geometry are tetrahedral.

Answer:

1. Tetrahedral for both electron and molecular geometries