If 4.8% is the answer then I messed up in a place where I wrote 0.8 instead of 0.08. This meant my other answers further down were also affected by this. How many marks will I lose for this? Will I only be marked down for the initial slip or will marks be taken away from the other answers as well?
I am a firm believer, when it comes to subjects like chemistry and biology, that one will only waste money on grinds. Let alone the fact that I had great teachers in these subjects, I feel that the textbooks are so comprehensive and easy to follow. Working hard on each chapter and understanding the material is vital and this is made easy by the great layout of information in the textbooks.
I got 4.8% for the concentration too, and 196,000 for Kc. My instantaneous rate was somewhere around 8 or 9 but they generally accept a range of values for that!
Regarding grinds, I agree with Insa333 - I don't think any grinds teacher could explain the material better than the textbooks do! It takes time and work but it all clicks eventually