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Understanding the element
Calcium (Ca) is chemical element 20. It belongs to the alkaline-earth metals, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.
Where do we encounter it?
In practice, it turns up most often in bones and teeth, cement and lime and biology.
bones and teethcement and limebiology
Standard atomic weight40.078(4)
What its position in the table tells us
Calcium sits in period 4, group 2 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.
Worth remembering
Calcium has a characteristic place in the periodic table that helps explain both its chemistry and its practical uses
Calcium has a characteristic place in the periodic table that helps explain both its chemistry and its practical uses