HELP WITH CHEMISTRY!!!?

okay so im chemistry we had a test on chapter two in the Raymond chang chemistry book. But he found out some people cheated and now we ALL have to take it over, and i don't remember what the chapter was on! AND i left my book at home! if anyone knows what the chapter is on and can tell me or can tell me a website that can help me out with the chapters from that book that would be great. thanks!