The interviewer is looking for your opinion on the most important piece of the Analytical Chemist position. While the position had many different components, there are two main aspects- the scientific piece, which involves knowing chemical compounds, standard lab practices and procedures, chemical hygiene, etc. and then there is the analytical piece, which involves compiling data, analyzing results, identifying errors, and a great deal of research. While all aspects of the position are important, the interviewer is looking to hear what you feel is the most important piece of the role. Provide details as to why you are choosing the particular piece that is most important to you.