Question

identify the correct lewis structure for so4^2-. select the single best answer.

Explanation:

Step1: Count valence electrons

Sulfur (S) has 6 valence electrons, oxygen (O) has 6 valence electrons. For $SO_{4}^{2 -}$, we have 1 S atom and 4 O atoms, and a 2 - charge. So the total number of valence electrons is $6+(6\times4)+2=32$.

Step2: Determine the central atom

Sulfur is the central atom as it is less electronegative than oxygen.

Step3: Connect atoms and distribute electrons

Connect the S atom to each of the 4 O atoms with single bonds first, using 8 electrons (4 single - bonds, 2 electrons per bond). Then distribute the remaining $32 - 8 = 24$ electrons as lone - pairs on the O atoms. Each O atom gets 3 lone - pairs. But to minimize formal charges, we can form double bonds between S and some of the O atoms. The correct Lewis structure has S in the center, bonded to 4 O atoms, with 2 of the S - O bonds being double bonds and 2 being single bonds, and appropriate lone - pairs on the O atoms.

Answer:

The Lewis structure has S in the center, double - bonded to 2 O atoms and single - bonded to 2 O atoms, with 2 lone - pairs on each of the double - bonded O atoms and 3 lone - pairs on each of the single - bonded O atoms. (Since no options are given, a general description of the correct structure is provided).