The discussion centers on calculating the number of moles and atoms of iron (Fe) in 400.0 grams. The initial calculation of 7.17 moles using the atomic weight of 55.8 g/mol was incorrect due to a lack of precision in the atomic weight and significant figures. The correct approach involves using a more accurate atomic weight for iron and applying Avogadro's number to find the total number of atoms. The importance of significant figures in the final answer is emphasized, as the original answer did not reflect the four significant digits of the given mass.
PREREQUISITESThis discussion is beneficial for chemistry students, educators, and anyone involved in quantitative analysis in chemistry, particularly those working with stoichiometry and atomic calculations.
Beats me. I would have said that's exactly what you're supposed to do. How do you know it's wrong? Were you given a different number as the solution?name_ask17 said:Ok. i attempted to find the number of moles by using 400/55.8 to get 7.17 but that is wrong?! please tell me ehy this is wrong. i set up a proportion like this 55.8g Fe = 1 mol
all over 400.0 grams =x and i solved for that x. i know its wrong, but why?
Maybe you should try a more accurate number for the atomic weight of iron. Also, what about the number of atoms question?name_ask17 said:well i know its wrong because my online homework is marking it wrong. I am really confused because i even tried changing the number to 4 sigfigs instead of 3 but it was wrong again. What am i doing wrong?!