all pre-university schools in singapore are well equipped for the syllabus required various science subjects - chemistry, biology and physics.
when I was studying A level chemistry in Singapore, I had 2h of chemistry lab per week, on top of my other science subjects (biology and physics). it adds up to 6h of lab per week, on top of all lectures and tutorials.
18h of lab for a pre-university science course sounds wierd. you don't need so much chemistry to prepare for university studies.