Question

Why plaster of paris should be stored in a moisture proof container?
1. because it will harden up if it will be left open.
2. because it increases in volume if will be left open.
3. because it decreases in volume if will be left open.
4. because it might catch fire if it will be left open.

Answer 1

Correct Answer - Option 1 : because it will harden up if it will be left open.

The correct answer is because it will harden up if it will be left open.

• Plaster of Paris should be stored in a moisture-proof container because it will harden up if it will be left opened.
• The plaster of Paris should be stored in a moisture-proof container.
• Plaster of Paris also called POP. 
• Chemically it is known as CaSO4.1/2H2O.
• Plaster of pars is a white coloured powder. 
• It is made up of gypsum.
• The plaster gets its name because its main ingredient gypsum is found abundantly in Paris. 
• The white powder will form a paste when it is mixed with water and it will harden into solid structures when dried.
• Uses: 
  •  In making casts for the manufacture of toys and statues.
  • In hospitals for making plaster casts to hold fractured bones in place while they set.
  • It is also used for making casts in dentistry.
  •  For making the surface of walls and ceiling smooth.
  • For making decorative designs on ceilings, walls, and pillars.
  • For making ‘chalk’ for writing on the blackboard.
  • For making fireproof materials.