rasen58

No, not really.

One gram of an element M combines with 3.9 g of chlorine. It forms an oxide with the formula M2O3. What is the element? a. Li b. Fe c. Al d. B e. Au What I'm confused about is how the grams impact the problem. I tried doing it without considering the grams and got it wrong, so I know they do something. Then I tried it like this. Chlorine has an oxidation of -1 and oxygen is -2 and because there are 3 oxygen atoms in the molecule, that means that the total charge on the oxygen is -6 which means that M must have a charge of +3. Aluminum is the only choice that has a charge of +3, but then what is the point of the first part of the sentence?

A 98 gram sample of silver oxide is heated in an open container until all the oxygen has been driven off. What is the total mass of silver remaining in the container? I used to know how to do such problems, but I'm not sure where to start. I know the mass of silver is 107.9 and oxygen's is about 16, so the molar mass of AgO would be 123.9 g/mol, but I'm not sure what to do after that.