A. Is wet calcined hemihydrate
B. Has porous and irregular crystals
C. Is a – hamihydrate
D. Has a W / P of 0.2
Related Mcqs:
- Plaster of paris is mixed in________________?
A. Plastic bowl
B. Rubber bowl
C. Glass bowl
D. Metal bowl - In plaster of paris the setting time is primarily altered by_________________?
A. Altering P / L Ratio
B. Altering temperature of mixing water
C. Speed and length of hand spatulation
D. Addition of accelerators and retarders - 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 - Water powder ratio of dental stone and plaster is respectively_________________?
A. 0.28 and 0.6
B. 0.6 and 0.28
C. 0.6 and 3.2
D. 0.28 and 0.98 - Green strength with reference to plaster means_____________?
A. Dry strength
B. Compressive strength
C. Strength of dental stone due to green colour
D. The wet strength - The main ingredient in dental plaster in_______________?
A. Calcium sulphate hemihydrate
B. Calcium phosphate
C. Calcium anhydrate
D. Calcium sulphate dihydrate - Powders of dental plaster and dental stone differ mainly in____________?
A. Solubility
B. Shelf life
C. Chemical formula
D. Particle porosity - Impression plaster containing potato starch is called______________?
A. Plaster of paris
B. Soluble plaster
C. Anti – expansion solution
D. Die stones - 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 - Plaster mix____________?
A. Rapid spatulation results in decreased setting time
B. 2% potassium sulphate is accelerator
C. Citrates are retarders
D. All of the above
