The goal of my job is education, which means the discovery, translation and dissemination of knowledge.
Education is the motivation for what I do in all three parts of my job as a professor: research, teaching and service. All three parts of the job are important to me.
Research allows me, selfishly, to expand my own knowledge. But it also allows me to expand the knowledge base of students, peers, the public, etc. – including those not born yet (how cool is that?!).
Teaching includes classroom teaching, mentoring undergrads, grad students, postdocs and visiting scientists in the lab, advising students and peers outside the lab, and providing international experiences. And teaching is all tied up with research. Research is a means to educate people in the lab on chemistry and what it means to be a responsible scientist (which includes teaching others).
Service roles I agree to take on (I don't agree to all) are aimed at facilitating the above, e.g., helping to improve classroom teaching, protecting and improving the welfare of students, helping colleagues in my department and around the world to have the means to pursue their own research/teaching endeavors. These activities generally involve expanding my own knowledge base, that of others engaged in the same service activities and that of the parties being served.