Look at the number of electrons on each model. The chart on the bottom wants you to match elements with electrons in the outer shell. There will be a couple of elements to match each model. For example, hydrogen is the first one on the chart. When you look up hydrogen on the Periodic Table you will see on the left hand side that it only has 1 electron in the outer shell (in fact it only has one). Anyway, that matches up with model B. The next element on the chart is Helium. Look on the Periodic table and you will find that it has 2 electrons in the outer shell. Therefore, the model match is C.
Last Updated: Friday, December 26, 2003