Writing on a high cpc keyword

Hii,

I have a blog monetized with ezoic, and it is a information site.

Was wondering if I write a article based on a high paying cpc ( eg like legal) and promote it using social media regardless of the article ranking on the organic search.Wont i be able to make good money?

If you write an article based on a different topic will ad networks display ads relevent for the written article right ?

It depends on your niche, your keyword, your website's look and feel, and so many other factors.
Best way to find out is to write one article, and to promote it on one social media platform that you know well. Based on the results, see if it makes sense to continue.

Thank you