Water powder ratio of dental stone and plaster is respectively_________________?

Related Mcqs:

1. Powders of dental plaster and dental stone differ mainly in____________?

   A. Solubility
   B. Shelf life
   C. Chemical formula
   D. Particle porosity

2. The main difference between dental stone and dental plaster is______________?

   A. Chemical composition
   B. Self life
   C. Sharpe and size of particles
   D. Solubility in water

3. The main ingredient in dental plaster in_______________?

   A. Calcium sulphate hemihydrate
   B. Calcium phosphate
   C. Calcium anhydrate
   D. Calcium sulphate dihydrate

4. Balanced stone is dental stone_______________?

   A. Which undergoes rapid expansion
   B. In which accelerators or retarders have been added according to need
   C. In which amount of water of hydration is controlled
   D. In which the crystals are all of uniform size

5. The water powder ratio of alginate is______________?

   A. 100 ml of water to 60 gms of powder
   B. 40 ml of water to 40 gms of powder
   C. 40 ml of water to 15 gms of powder
   D. 15 ml of water to 40 gms of powder

6. Model plaster (white) used to cast study models before mixing with water, is largely composed of____________?

   A. CaO
   B. CaCO3
   C. (CaSO4)2-½H2O
   D. CaSO4-2H2O

7. High copper dental amalgams are superior to other amalgams because high copper dental amalgems______________?

   A. Have less marginal breakdown
   B. Are workable at lower Hg-alloy ratio
   C. Have a higher ratio of tensile to compressive strength
   D. Have less resistance to tarnish and corrosion

8. The American dental association (ADA) specification number for non-aqueous elastomeric dental impression material is______________?

   A. 19
   B. 20
   C. 21
   D. 26

9. What is the polymerization shrinkage if 3:1 powder: liquid ratio is used____________?

   A. 6%
   B. 8%
   C. 10%
   D. 21%

10. The β (Beta) hemihydrate of gypsum requires more water to float its powder particles because______________?

    A. They are more regular in shape and dense
    B. They are more regular in shape and highly porous
    C. They are more irregular in shape and porous
    D. They are more dense and prismatic in shape