What's New

iOS 15 fixes- minor content updates

App Description

Why are some triatomic molecules linear (carbon dioxide, hydrogen cyanide) and others are bent (water, sulfur dioxide)? And why is the bond angle in water (~105°) smaller than that in sulfur dioxide (~119°)? Valence Shell Electron Pair Repulsion (VSEPR) theory provides surprisingly simple explanations in terms of the electron pairs that surround the central atom of a given molecule. VSEPR theory is described in detail in every introductory chemistry book.

The ODYSSEY VSEPR Theory app provides three-dimensional models of 50 small molecules and ions as well as a set of generic models that illustrate the conceivable geometries of the theory. Each model can be moved and manipulated with simple touch gestures. Bond lengths and bond angles can be queried.

Users can pick from multiple model styles (such as Ball and Spoke or Space Filling), request a schematic display of lone pair positions, and show the molecular dipole arrow. A glossary, comments section, and a set of multiple-choice questions (with randomized options) are also available.

Most learners of chemistry are visually oriented. Complementing the presentation found in any introductory textbook, ODYSSEY VSEPR Theory enables exploration of one of the most fundamental concepts in general chemistry—molecular shape.

iPad Screenshots

(click to enlarge)

ODYSSEY VSEPR Theory screenshot 1 ODYSSEY VSEPR Theory screenshot 2 ODYSSEY VSEPR Theory screenshot 3 ODYSSEY VSEPR Theory screenshot 4 ODYSSEY VSEPR Theory screenshot 5

App Changes

  • June 15, 2014 Initial release
  • October 13, 2014 New version 1.0.1
  • December 04, 2014 New version 1.0.2
  • January 21, 2016 New version 1.0.3
  • June 15, 2019 New version 1.0.4
  • September 16, 2023 New version 1.0.5

Other Apps From Wavefunction, Inc.

iSpartan ODYSSEY Atomic Orbitals ODYSSEY Resonance ODYSSEY Electron Sharing ODYSSEY Polar Bonds- Molecules ODYSSEY Basic Crystal Lattices ODYSSEY Ionic Solids ODYSSEY Common Substances ODYSSEY Chemical Elements ODYSSEY Functional Groups ODYSSEY Crystal Surfaces ODYSSEY Water: Molecular Level ODYSSEY Ionic Bonding ODYSSEY States of Matter ODYSSEY Intermolecular Forces