Page 45 - The Periodic Table Book

Uses CALCIUM CAVES

As running water flows into caves, it deposits
This tablet contains
calcium carbonate, which calcium carbonate. These deposits build up to
is an alkali – a substance form structures called stalactites and stalagmites.
that balances out acids.
Water with dissolved calcium carbonate
flows through a crack and into the cave.
Antacid
tablets
Sea shell
Stalactite hangs
from the ceiling. Alkaline Earth Metals

Stalagmite
grows up from
the ground.
Water drips Over time, calcium carbonate
onto the starts to build up on the
ground. ground and ceiling.
An adult
human contains
about 1 kg (2 lb)
of calcium Plaster cast
Shells of sea in the body.
snails are hardened
by calcium carbonate
absorbed from
sea water.

This plaster of Paris cast hardens
Writing chalk
when dry, supporting broken bones.

Calcium-rich
food

Milk These chalks contain
calcium sulfate.

Marble forms The Sphinx, Egypt
when limestone
comes under high
temperature
and pressure. Marble statue

Broccoli

Orange This statue is made of
limestone, a natural rock
containing calcium carbonate.

Oranges are also a good source of calcium, and construction materials. Plasterboard, which
most orange juices have extra calcium added to is used to make walls smooth, writing chalk,
them. Antacid tablets, used to settle and Plaster of Paris are all made from the
indigestion, contain calcium carbonate. This mineral gypsum. Calcium oxide is an
compound reacts with acid in the stomach. important ingredient in cement and
Calcium compounds are also common in helps turn it into hard concrete. 43

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