college credits overlapping?

Say you want to earn two undergraduate degrees (Associates or Bachelors degrees), either both at the same time or one after the other. All degree programs have certain general course requirements in common. As a rule, one of those requirements is a laboratory science; in this case, chemistry. Assuming these programs do not each specify a different course, then the same course will satisfy both requirements, and you need take it only once. But if one program requires, say, Organic Chemistry and the other requires Inorganic Chemistry, then you would have to take both.

If you complete a Bachelors degree and decide to go to graduate school for a Masters and/or a Doctoral degree, you start over again at the graduate level. An undergraduate-level chemistry course may be a prerequisite (meaning you must have already passed it in order to enroll in a graduate-level course), but it will not satisfy the graduate-level requirement.

Your best bet is to consult your academic adviser. It is the adviser's job to help you select courses that meet your requirements.

I'm not sure what a 'professions' major would be. Here are the possible degrees you can earn:

Associates = 2 years

Bachelors = 4 years OR associates + 2 years

Masters = bachelors + 2-3 years

PhD = bachelors + masters + 2-6 years

Not all schools require you take chemistry, but a few might. You'd be doing one degree at a time, and the credits would go towards that degree. You can often apply the credits from an associates towards a bachelors, but not to a masters or PhD.

Yes, ie, if you are trying to get a degree in biology and chemistry (both require chemistry courses) they would count for both majors.

It is really hard to understand what you are asking, but I can assume you are asking about your credits for college? go to any college website,and they will tell you the requirements for the particular major you are talking about

yes