Answer:
Na has atomic number 11
which is less than magnesium has atomic number 12
ANSWER IS D
Explanation:
aluminum or Al is atomic 13 and Ca or calcium is atomic number 20 and rubidium or Rb is atomic number 37
One possible answer could be that a chemical reaction has occurred.
It is often a sign of kidney problems. :)
An not sure,, but maybe 24. don't take my word for it