Question

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 1

Lorenzo is incorrect. Xenon is a noble gas, and iodine is a halogen. Halogens are way more reactive than noble gases (and xenon is one of the least reactive of those). You also have to pay attention to the families and the number of electrons in the valence shell when making these predictions.

Answer 2

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.