These are not actual sections of the courses. Rather, they are overflow/holding sections that assist the Chemistry department in accommodating as many students as possible in their courses. Students in these sections will be assigned to another existing (but full) section during first week of classes (please do not email your instructor about getting assigned to a section before the first week of classes).
If you are registering for one of these sections, make sure that at least one of the full sections would fit your schedule. If none of the sections of the course fit your schedule, then registering for the overflow section will not help you and you will not be able to take the course.
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