Lorenzo is making a prediction. “I learned that nonmetals increase in reactivity when moving from left to right. So I predict that xenon will be more reactive than iodine.” Is Lorenzo correct? If so, why? If not, explain his error.

Answer:

Lorenzo is not correct. Nonmetals increase in reactivity from left to right because nonmetals on the right have more valence electrons. They need to gain fewer electrons to have a full outer shell. However, this trend only continues until group 17, because the noble gases already have a full outer shell. Therefore, their reactivity is the least of all the elements.