I believe one should0 start building up his professional experience as soon as possible after B. Sc. And he can simultaneously go for a M. Sc. while keeping his experience meter running and having an income at least to fund his research, properly.
After all, HR people does put practical experience before academic achievements!
Mohamed Khader i know that you can't take your master degree in chemistry and work together because if you are going to conduct a research to write a thesis that will consume your time and will require you full attention beside the courses you are going to take you will not have the time for job, study and research. the only job good in such sitiuation is teaching.
