"To Whom It Concern" is not an option!! What is the best format to address/title a grad school statement of purpose?

The grad school statement of purpose is different from the undergrad. What you write is more like an academic job cover letter rather than a high school essay. In it you should be very specific about your work. Give technical details, none of this "I enjoy..." The people reading your application are professors serving on the departments graduate admissions committee headed by the director/chair of graduate studies. This person has a name. He is "Professor and Chair" But you can also address it to the Committee.

Use something like "Dear Chemistry Graduate Program" or "Dear Dr. Smith - Head Graduate Program".

You don't normally address a statement of purpose like a letter, unless the instructions specifically tell you to. Title it "Statement of Purpose" Put your name in the upper corner or centered under the title.