As a student, I used to be terrible with Chemistry. The alphabets, the numbers, the arrows, the deductions! Damn, I never knew how to place them together. All the right alphabets, all the right numbers and all the right equations. But if anyone ever dared turned any of my equations practical, I'm sure we'd have a huge, explosion of red smoke and blindness.
Coming to think of it, I'm still quite bad with chemistry. All the right equations. All the right people. And all the right signs. But once again, if anyone dares turn any of these equations practical...;)