According to your experience as a chemist how many experiments made by a chemist per year are useless ?
Our definition of a useless reaction is the following :
- not working, and could be anticipated : a lot of people have tried it (or very similar) all over the world and it's not working for sure, but the knowledge is not accessible
- a calculation error has been made, preventing to obtain the desired product
Please put only a number of reactions, no scales, no percentage. Thank you.