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A cup of Calcium a day, keep the teeth and bones from breaking away!

Goal: You will meet Calcium (Ca) and Magnesium (Mg). Tom-the-Atom continues teaching you, Mary, and Henry how to “read” the Periodic Table.

Tom-the-Atom introduces representatives of the Alkaline Earth family, Column 2 in the Periodic Table, Calcium (Ca) and Magnesium (Mg). Atoms from Group 2A have only two Valence electrons (Column 2) in their outermost shell. They prefer to lose them and keep their inner shell full, to be stable, rather than hunting for six additional Valence electrons and filling up their outermost shell with 8 Valence electrons. When the atoms lose two electrons, the atoms became charged twice positively (because they lost two negative electrons). They are called divalent positive ions (divalent Cations). 

Both Calcium and Magnesium are essential for the well-being of human bones, teeth, and nervous systems, and they are contained in milk and many fruits.


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