Justin Wu: head of Ace Chemistry for a reason, explains concepts in great depth and has very engaging lessons. Keep in mind he only has one class for year 12 and that is accelerated.
Joel: has really good tips with how to understand content and is the second best teacher at Ace.
Jake: Goes into good depth and helps a lot with school assessments. Third best, if you don't get Joel or Justin, I recommend Jake.
Hope this helps!