Question about CPC

Hey guys, I've been lurking these forums for some time now and I've been learning alot, I have one question:

I have a website on a niche for which the main keywords go from 7 to 40 dollars cpc (USA), but I earn 1 dollar per click (USA), and I don't understand how is that supposed to be,

is the ad from adsense related to the keywords on my website? or is the ad related to what the visitor searched before coming to my website?

Thank you

CPC is for advertisers, adsense pays much less and splits between Google and publishers.

oh I didn't know that, thank you, I thought we could estimate how much we could make on a given keyword by using google adwords planner, didn't know it could go so far off.