For this problem, we need to compare the formal charge of each structure.

Recall that the formula for the ** formal charge** is:

$\overline{){\mathbf{F}}{\mathbf{.}}{\mathbf{C}}{\mathbf{.}}{\mathbf{=}}{\mathbf{Group}}{\mathbf{}}{\mathbf{Number}}{\mathbf{-}}{\mathbf{(}}{\mathbf{Bonds}}{\mathbf{+}}{\mathbf{Nonbonding}}{\mathbf{}}{{\mathbf{e}}}^{{\mathbf{-}}}{\mathbf{)}}}$

SeO_{4}^{2-}

** Group Valence Electrons**

Se 6A 1 x 1 e^{-} = 6 e^{-}

O 6A 4 x 6 e^{-} = 6 e^{-}

-2 charge +2 e^{-}

Total: **32 valence e ^{-}**

**Structure 1:** The given Lewis structure is:

Total # of electrons = (2 e^{-} x 6 bonds) + (2 e^{-} x 9 lone pairs)

Total # of electrons = 30 e^{-}

**The structure is not the best Lewis structure for SeO _{4}^{2-}.**

**Structure 2:** The given Lewis structure is:

Total # of electrons = (2 e^{-} x 4 bonds) + (2 e^{-} x 13 lone pairs)

Total # of electrons = 34 e^{-}

**The structure is not the best Lewis structure for SeO _{4}^{2-}.**

**Structure 3:** The given Lewis structure is:

Total # of electrons = (2 e^{-} x 6 bonds) + (2 e^{-} x 9 lone pairs)

Total # of electrons = 30 e^{-}

**The structure is not the best Lewis structure for SeO _{4}^{2-}.**

**Structure 4:** The given Lewis structure is:

Choose the best Lewis structure for SeO_{4}^{2-}.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Formal Charge concept. You can view video lessons to learn Formal Charge. Or if you need more Formal Charge practice, you can also practice Formal Charge practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Laviska's class at SHU.