Page 44 - Curriculum Visions Dynamic Book

Key facts about...
Calcium
Essential for plant and animal growth
Calcium carbonate is insoluble in water
Forms the minerals that make limestone rocks
Is part of the bones and shells of all animals
Found most commonly as calcium carbonate, calcite
SHELL DIAGRAMS
The shell diagrams on these two pages are representations of an atom of each element. The total number of electrons is shown in the relevant orbitals, or shells, around the central nucleus.
Electron shell
Electron
Nucleus containing protons and neutrons (called nucleons)
 These huge stalagmites in Big Room, Carlsbad Caverns, New Mexico, are the result of calcium carbonate precipitation over thousands of years.
A soft, silvery-coloured metal, chemical symbol Ca
Atomic number 20, atomic weight about 40
Fifth most plentiful element at the surface of the Earth
Calcium bicarbonate dissolved in cold water causes “temporary hardness”
Makes up over 3% of the Earth’s crust
44 44