I would like to use the id selector:
$("#id")
Is there a way to do this only for the nth element with this id on the page? i.e.
$("#id:n")
A page can have only one element with a given identifier.
From the HTML standard :
The document should not have several elements having the same id.
Now suppose you want to get the nth element with a given class on your page, you can use eq :
$('.myclass').eq(index)
You can do the following:
$("#id:eq(n)")
But, as @dystroy answer, it should be only 1 id per page, so you better use a class.
You can use the :eq(n) selector to get the nth element, but the identifier must be unique.
:eq(n)
You must use the class attribute to group similar elements.
class