Alkaline+Earth+Metals+by+Dillon,+Michael,+and+Brady

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 * Calcium ** is an Alkaline Earth metal. Its Symbol is Ca. I was named after a Latin word calcis and discovered by Sir Humphrey Davy in 1808.The atomic number is 20 and its atomic mass is 40.078 with a melting point of 830 degrees Celsius and boiling point 1484 degrees Celsius. Its valence number is 2. It has many uses such as it is a life form for bones, chalk, and limestone. Calcium is silver and has a crystal cube structure. Men and women need 1,000 to 1500 mg a day. Dairy products are rich in calcium. by Brady Marienau