Page 15 - Curriculum Visions Dynamic Book

 Stalagmites, Carlsbad Caverns, New Mexico.
 Small wind-distorted stalactites, Caverns of Sonora, Texas.
mineral-laden: a solution close to saturation.
percolate: to move slowly through the pores of a rock.
 When water drips
out of cracks in a cave, some of the carbon dioxide gas escapes from the water and
the calcium bicarbonate changes to calcium carbonate (insoluble limestone). This is precipitated as a tiny addition to the cave. This picture shows a dripping limestone stalactite, Jenolan Caves, Australia.
Oxygen
Carbon
Calcium
EQUATION: Precipitating limestone
Calcium bicarbonate (soluble)
Carbon dioxide
15 15
Water
Calcium carbonate
Hydrogen
Calcium bicarbonate ➪ carbon dioxide + water + calcium carbonate
Ca(HCO3)2(aq) ➪ solution
CO2(g)
+
H2O(l) +
CaCO3(s) precipitate