These quizzes (legacy.chemgym.net) are distributed as Freeware.
You may use them for individual study, place them on a network in an educational institution, put copies on floppy disk or CD-ROM and give them away to students and staff, provided only that you leave the copyright message on the main index page unchanged.
You are free to alter the content of any of the pages (except the copyright message on the main index page) and add new pages of your own, but you may not distribute the quizzes for any financial gain.
If you have any suggestions for other ways to distribute the quizzes or find yourself in doubt about any aspect of the Terms and Conditions, please contact me at mike.docker@gmail.com.