A student attempts to arrange four elements (as shown below) in order from most reactive to least reactive. Is the arrangement correct, and why (or why not)?
19 12 6 2
K MG C HE
39.10 24.31 12.01 4.00
(1 point)
The correct order from most reactive to least reactive is:
K > MG > C > HE
This is because the reactivity of elements generally increases as you move down a group in the periodic table. In this case, Potassium (K) is the most reactive, followed by Magnesium (MG), Carbon (C), and Helium (He) which is the least reactive. So the arrangement provided by the student is correct.
Is the arrangement correct, and why (or why not)?
(1 point)
Responses
Yes. An element’s reactivity decreases along with its atomic number.
Yes. An element’s reactivity decreases from left to right on the periodic table.
No. An element’s reactivity decreases from right to left on the periodic table.
No. An element’s reactivity decreases as atomic mass increases.
No. An element’s reactivity decreases along with its atomic number.
This is the correct explanation because an element's reactivity generally increases as you move down a group in the periodic table (with increasing atomic number), not from left to right or as atomic mass increases.