A student attempts to arrange four elements (as shown below) in order from most reactive to least reactive.
K>Mg>C>He
Is the arrangement correct, and why (or why not)?
(1 point)
Responses
A. Yes. An element’s reactivity decreases along with its atomic number.
B. Yes. An element’s reactivity decreases from left to right on the periodic table.
C. No. An element’s reactivity decreases as atomic mass increases.
D. No. An element’s reactivity decreases from right to left on the periodic table.
B. Yes. An element’s reactivity decreases from left to right on the periodic table.
This is because elements on the periodic table are arranged in order of increasing atomic number. As you move from left to right, the number of protons and electrons increases, leading to stronger interactions with other elements and therefore increased reactivity. So, the correct order from most reactive to least reactive in this case would be He<C<Mg<K.