Question

Try to collect the information to reasons for calling calcium sulphate hemihydrates as plaster of Paris (pop)

Answer 1

Answer:

Plaster is the common name for calcium

sulphate hemihydrate(CaSO4.1/2H20) made by

heating the mineral gypsum, the common name

for sulphate of lime. Plaster was first made about 9000 years ago, and has been used by ancient

Egyptian, Greek and Roman civilizations.

However, it wasn't used on a large scale until

1700s, when it was required to be used in all

construction in Paris.

In 1666, a fire raged across London, destroying many parts of it. In its aftermath, the king of France ordered that all walls made of wood in Paris be immediately covered with plaster, as a protection against such fires. This resulted in large-scale mining of gypsum which was available around Paris in huge quantities. Thus, during the early 18th century, Paris became the centre of plaster production, and hence the name, plaster of Paris.

Source:Why is the plaster of Paris called so? -

The Times of India

Answer 2

Short Answer:

Calcium Sulphate hemihydrate is called plaster of Paris (can be written as POP) because as we have seen in the above reaction, it is formed by heating Gypsum at the temperature 373K to 400K . The name plaster of Paris is derived from the large deposits of gypsum in the Montmartre hill in Paris.