A comment on concentration- Too many people focus on time spent studying, instead of goals. This is bad for two reasons:
1. Work expands to fit the time allocated. Thus, you might work slower/less efficiently because you know you have to sit down for X hours.
2. If you become tired, your study is instantly unproductive. But you are forcing yourself to sit down for X hours, which is a waste of your time.
Focus on doing goals. For example, today I want to finish a document that I have on past HSC chem questions. As soon as I finish that, I'm not planning on doing more study. Thus you become efficient because you have an incentive to finish. Also, as soon as I realise that I can't concentrate, I stop studying. Go for a run, watch some t.v., do anything to clear your mind. Then come back in about an hour. If you just try and push through a mental block, you're just wasting your time.
