... However, if you can actually get work experience, it's a great thing to add (before I forget to say that
).
Extra-curricular parts can vary depending on what you've done and how much else you already have in your personal statement. If you are well over the line limit, then yes, extra-curricular should be the first to be cut down, but I do recommend having two or three lines just to prove you do something outside of chemistry (and as I always say, relate the extra-curricular activity back to your studies in chemistry. Whether it be improving time management, team working, planning...)