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Home Concept Builders Chemical Bonding and Molecular Shape Valence Shell Electron Pair Repulsion Theory Help Help 2

Valence Shell Electron Pair Repulsion Theory - Questions 2 Help

The shape of a molecule can be predicted from the Lewis electron dot diagram. By inspecting the number of groups of electrons AND the number of atoms that surround the central atom of the molecule, the shape of the molecule can be predicted.

There are three versions of questions in this Question Group. Each version is very similar the others. They only differ in terms of the order in which the molecular formulas are given. Here is one of the versions:
 

Version 1:
One of these molecules has a shape that is not like the others. Which one doesn't belong? Begin by identifying the correct Lewis electron dot structure. Then identify the one structure that leads to a molecular shape that is different than the other two.
 
NH3
BH3
CO32-

To be successful on this question, you must complete two tasks. First determine the correct Lewis electron dot diagram. And second, determine the molecular shape of the three molecules. Pick as an answer the molecule that has a shape that is different than the other two.

This page does not discuss the Lewis electron dot diagrams. You will find help with that on a separate page. View Lewis Electron Dot Diagrams page.

The graphics below represents our help with molecular shape. The model used to predict the shape of molecules is known as the Valence Shell Electron Pair Repulsion Theory. The graphics describe this theory and give three sample analyses. The table that follows the three analyses is very important. Study the table and use it to help you answer this question.







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