wunder beta

📘 Begin with a Lewis structure

Start with a Lewis sketch, not a photo. Mark every bond and lone pair on the central atom before you name a shape.

3
lessons
~15 min
to learn
Adults
level
Start the course →

What you’ll learn

  1. Count the regions around the centerUse a Lewis structure to count VSEPR electron domains around a central atom.VSEPR needs an electron inventory before it predicts a shape. Bonds and lone pairs are regions of electron density, and multiple bonds still count as one region. The total is the steric number that selects an electron-domain geometry.
  2. Place the electron domainsConnect steric number to the standard electron-domain geometries.Electron regions spread out to reduce crowding. Two make a line, three make a flat triangle, four point toward a tetrahedron, and five or six create larger standard arrangements. These are complete arrangements before lone pairs are hidden from the molecular-shape name.
  3. Hide the lone pairs to name the shapeDistinguish electron-domain geometry from molecular geometry and predict common molecular shapes.Molecular geometry reports where the atoms sit, while electron-domain geometry includes lone pairs. That distinction explains why four domains can produce tetrahedral, trigonal pyramidal, or bent molecules. A consistent count-and-hide routine works beyond memorized examples.

Questions this course answers

In VSEPR, how many electron regions does a double bond count as?

A single, double, or triple bond occupies one direction from the central atom, so each is one electron region.

Complete the rule.

Nonbonding electrons occupy space around the center and must be included in the domain count.

Put the VSEPR routine in order.

Start with the Lewis structure, count domains, arrange them to minimize crowding, and then name the atom-only shape.

Match each formula to its molecular geometry.

The visible shape depends on the number of bonding regions and lone pairs around the central atom.

Why is water called bent rather than tetrahedral?

Water has tetrahedral electron-domain geometry, but its two visible hydrogen atoms occupy only two of those four positions.

Grounded in trusted sources

  • [object Object]
  • [object Object]
  • [object Object]
  • [object Object]
  • [object Object]

Every Wunder lesson is built from real, reputable sources — never invented.

Related courses

📘Electronegativity is an atom's pull in a bond📘Enthalpy change tracks heat at constant pressure📘Split the diagram into two half-cells📘Start with A = epsilon b c📘Start with the baseline and solvent front📘Turn curiosity into a testable question📘A conclusion answers the question with evidence📘Reaction rate is concentration change per time

Wunder is a personalized learn-anything platform — tell it any topic and it builds a beautiful, fact-checked course in minutes, with narration, a knowledge check, and a college-style University track.

All topics · Home

© 2026 Wunder Learning LLC · Terms & Privacy