Question

Choose the correct option regarding the uses of Plaster of Paris.

• A. It is used for making glass
• B. It is used in soda-acid fire extinguisher.
• C. It is used by doctors for supporting fractured bones.
• D. It is used for making soaps.

Answer 1

The correct option is C It is used by doctors for supporting fractured bones.

Plaster of Paris $\left({\text{CaSO}}_4.0.5{\text{H}}_2\text{O}\right)$ is a white powder which on mixing with water sets into hard solid mass due to formation of gypsum$\left({\text{CaSO}}_4.2{\text{H}}_2\text{O}\right)$.

${\text{CaSO}}_4.0.5{\text{H}}_2\text{O}+1.5{\text{H}}_2\text{O}\to {\text{CaSO}}_4.2{\text{H}}_2\text{O}$

Therefore, Plaster of Paris is used for supporting fractured bones in the right position.

Washing soda is used for making glass, papers and soap.

Baking soda is used in soda-acid fire extinguisher.