Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray alkaline earth metal, fifth-most-abundant element by mass in the Earth 's crust. The ion Ca 2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.Free calcium metal is too reactive to occur in nature.ith a density of 1.54 g/cm 3, calcium is the lightest of the alkaline earth metals; magnesium (specific gravity 1.74) and beryllium (1.84) are denser though lighter in atomic mass. From strontium onward, the alkali earth metals become denser with increasing atomic mass.
In 1933, United Detroit Theaters acquired the Michigan from Paramount-Publix/Balaban & Katz, who had in turn, purchased it from Kunsky. By the end of the 1930âs, both the live stage shows and the grand Wurlitzer organ were gone, and the theater featured only movies.
The phone number of the Detroit Children'S Museum is: 313-873-8100.