If something contains large amounts of cyclopentane and cyclohexane, what is it called? I'd like to know what is the something as well. It's a chemistry olympiad question for this year. See here, Question 3-g. Just let google translate it for you. I find some questions quite weird as well, but what can you do. Otherwise its pretty good.
The most likely name would be naphthenes. It could also be called cycloalkanes.
Since the reference to the question is about the coal and oil production, the answer would be naphthenes. When the coal and oil were distilled, a layer (called naphthene) was removed which was found to contain mainly cyclopentane and cyclohexane.
I would complete the statement as:
If a fraction of distillate contains large amounts of cyclopentane and cyclohexane, it is called naphthene.