Final answer:
The compound prepared from gypsum that hardens when mixed with water is called calcium sulfate dihydrate or gypsum. Its chemical formula is CaSO4 · 2H2O.
Step-by-step explanation:
The compound prepared from gypsum that has the property of hardening when mixed with water is called calcium sulfate dihydrate or gypsum. Its chemical formula is CaSO4 · 2H2O. The chemical equation for its preparation can be written as CaSO4 · 2H2O + heat → CaSO4 + 2H2O.
One use of gypsum is in the construction industry, where it is used for making plasterboard, which is commonly used as drywall or wallboard in buildings. Gypsum is also used in agriculture to improve soil quality and promote plant growth.