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The Molecular Editor is easy to use and has a help section. Structural formulas are created in the drawing window. The menu bar of the drawing window allows you to draw single, double or triple bonds and different sized rings. Hetero atoms, such as N, O, F, Cl, S & Br may be designated by the left-side menu. Do not attempt to draw hydrogens; they are automatically provided for hetero atoms. Hydrogen, metals and other elements not on the menu bar are designated by the X button, which opens a small text window in which the symbol may be entered. Stereoisomers are distinguished by this program, either by using the wedge drawing tool or by specifying the configuration of double bond substituents.
Select an example on the left, draw the structure in the editor on the right, then press the Check Answer button.

Example 1. CH3(CH2)3CH(CH3)2 Example 2. Example 3. Example 4. * Example 5. Example 6. * The editor also accepts a nitro group representation having two N:O double bonds, even though this violates the octet rule.