In 500 words, tells us about what makes you, you. What are you strengths, weaknesses, and your motivation? What separates you from any other applicant? How do you think HU will increase your strengths and diminish your weaknesses?
this is the admission essay question i need to answer. for the other schools it was basically one question, this one is difficult because i do not know exactly how to answer it. should i split each question into a paragraph or would that be too all-over-the-place?
These are good questions! I think a paragraph on your strengths, with examples to back them up, a paragraph on your weaknesses (doesn't have to be as long! ;-)) and perhaps combining your motivation with what separates you from other applicants -- that might work well. Then another paragraph for the final question about HU, which can probably also serve as your conclusion.
If, after writing it, you feel it's too all-over-the-place, you can always try combining paragraphs, but it seems to me that if you are answering the specific questions asked, you will be right on target.