Sodium is a chemical element with symbol Na and atomic number 11. It is a soft, silver-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is ²³Na.
Magnesium is a chemical element with symbol Mg and atomic number 12. Its common oxidation number is +2. It is an alkaline earth metal and the eighth-most-abundant element in the Earth's crust and ninth in the known universe as a whole.
Aluminium is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery white, soft, ductile metal. Aluminium is the third most abundant element, and the most abundant metal in the Earth's crust.
Silicon is a chemical element with symbol Si and atomic number 14. It is a tetravalent metalloid, less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table
Phosphorus is a chemical element with symbol P and atomic number 15. A multivalent pnictogen, phosphorus as a mineral is almost always present in its maximally oxidised state, as inorganic phosphate rocks.