November 1, 2014 (Vol. 34, No. 19)


Strong Points: Interactive education
Weak Points: Not much of a tutorial given




If you think back hard enough to your very first chemistry class, maybe you’ll remember drawing out Lewis electron dot structures when you were first learning about chemical bonds. Nowadays, students have it easier because the Chemical Valence app makes the concepts of valence and shared electrons more intuitive via an interactive interface. Here, students drag electrons from different atoms together to “draw” Lewis electron dot structures and build molecules. Once the electrons are placed in the correct positions, bonds form and ultimately the app displays a 3D rendering of the newly created molecule. The exercises proceed in increasing complexity and difficulty, from the formation of single bonds and lone electron pairs, to multiple bonds and small molecules, to polyatomic anions, and finally to octet exceptions.

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