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Reporting a chemistry error

If you believe an answer, hint or explanation is wrong, please include the compound name shown in the exercise, a description of the structure you drew, and the feedback you received. Reports are checked against the structure, and corrected exercises get a new revision number.

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The aim is for every page, button and feedback message to work with a keyboard and a screen reader. The drawing canvas itself is a visual editor and cannot be used without sight; if that stops you from using the site, please get in touch.

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The site does not keep accounts or store your practice data on a server. For any privacy question, use the address above.