Learning how to look up an answer will benefit you far more than reading what someone here thinks it is. From the simplest post a general chemistry student asks to this, how much time did you take searching for the answer? I don't know, but I could look it up for you; the fact of the matter is you won't learn anything unless you learn how to find the answers yourself. Stop delaying the inevitable because it will eventually catch up to you. In addition, your question is ambiguous which I think further proves my point about you needing to learn how to ask people (and search engines) questions in a more succinct manner. I hope this helps because it will be the most important skill you will take away from working on problems like this.