It's not exactly homework, as we've already finished the test, but I'm posting it here anyways. I've verified that I got most of the questions right, but there are still some I'd appreciate some input on. Warning: This is easy chemistry. By the way, the test was given in Norwegian, and I am a little unsure about the names of certain bonds and other chimcal things in English, but I'll try, and I hope you understand it. So here we go. First: We were asked about "three main kinds of chemical bonds". What kinds of bonds are the main ones? We were also told to use the term "electronegativity" in our description. Secondly: We were supposed to find the chemical names and the trivial names of a few substances. I've done this, and got them correct, but then the task asks for the ions in the substances that are ionic bonds. Which of these are ionic bonds, and which are not? And why? Na2O, HCl, CaCO3, H3PO4, Mg(NO3)2 And then we were to explain how we find the formula of the product when two chemical elements react. I know how to do it, and I've done all the tasks correctly, but I feel that my explanation was rather weak. How would you have put it? Thanks a lot for all replies!