2017 · Q19
The paste of a white material in water is used to maintain a fractured bone fixed in place. The white material used is called
General KnowledgeChemistry
- Ableaching powder
- Bplaster of Paris
- Cpowder of zinc oxide
- Dlime powder
Explanation
Fractured bones are immobilized with a cast made from plaster of Paris, which is calcium sulphate hemihydrate (CaSO₄·½H₂O). When its paste in water is applied, it sets into hard gypsum, holding the bone rigidly in place while it heals. Bleaching powder is a disinfectant, zinc oxide powder is used in skin ointments, and lime powder has no orthopedic use. The white material is therefore plaster of Paris.