It's a language problem.
In English there apparently are no specific words to make the difference between what f.i. the Alps are and what the Dolomites are. Both seem to be ranges.
could be a language thing - realistically, i would argue that the term 'chain of mountains' is not really used in english - in spanish, perhaps, the Alps are a Cordillera and the Dolomites are a Cordon - i can't say for italian, french, german, etc.