How can I apply the knowledge I learn in lessons to tougher exam style questions ?

The million dollar question when it comes to chemistry and is often the difference between a good grade and a great grade. The basis of this is to consolidate your basic concepts, make sure those are instilled within your chemistry thinking.(Flash cards are a great way to go about this) Then practice, practice, practice but when doing questions, at least at the start have your notes open so you can get a feel of how the basic concepts tie in. Whilst studying mark schemes to see exactly what the examiner's want. If you follow this and build up your confidence then those tough application questions will no longer bother you.