Q.1:
Model plaster (white) used to cast study models before mixing with water, is largely composed of____________?m
A.
CaO
B.
CaCO3
C.(CaSO4)2-H2O
D.
CaSO4-2H2O
Q.2:
Water powder ratio of dental stone and plaster is respectively_________________?P
A.0.28 and 0.6
B.
0.6 and 0.28
C.
0.6 and 3.2
D.
0.28 and 0.98
Q.3:
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
Q.4:
Water of reaction needed to react completely with 100 g of calcium sulphate hemihydrates to convert it to calcium sulphate dihydrate______________?
A.18.6ml
B.
22.2ml
C.
30.4ml
D.
45.3ml
Q.5:
Plaster of paris is mixed in________________?-
A.
Plastic bowl
B.Rubber bowl
C.
Glass bowl
D.
Metal bowl
Q.6:
Die is________________?
A.
Impression of single tooth
B.
Impression of whole teeth
C.Replica of single tooth
D.
Replica of whole teeth
Q.7:
The main ingredient in dental plaster in_______________?8
A.Calcium sulphate hemihydrate
B.
Calcium phosphate
C.
Calcium anhydrate
D.
Calcium sulphate dihydrate
Q.8:
Accelerators and retarders are used with gypsum products mainly to control_______________?Z
A.Setting time
B.
Setting expansion
C.
Hardness of the set product
D.
None of the above
Q.9:
The hygroscopic technique is associated with______________?;
A.Investment
B.
Hydrocolloids
C.
Amalgam
D.
Silicate
Q.10:
The most commonly used accelerator in gypsum product is___________________?K