801. The principal corrosion product of dental gold alloys that contain silver, is?
A. silver chloride
B. silver sulfide
C. hydrogen sulfide
D. silver dioxide
802. In noble metal casting alloys, platinum may be substituted by the
A. palladium
B. carbon
C. gallium
D. nickel
E. Iron
803. Alginate Impression materials datrioraterapidly at elevated temperatures, probably due todepolymerization of the alginate constituent?
A. Both the statement and reason ere correct
B.The statement is correct but reason is not correct
C. The statement is not correct but the reason is correct ‘
D. Both the statement and reason are incorrect
804. Patients dislike the odor and taste of which Impression material?
A.Polysullides
B. Polyethers
C. Alginates
D. Addition silicones
E. None of the above
805. Which of the following materials would have the least change in dimension because of changes inmouth temperature?
A. Acrylic resin
B. Gold inlay
C. Composite resin
D. Amalgam
E. Silicate cement
806. If porcelain is to be fused to metal, which of the following properties of porcelain and metal shouldbe similar?
A. Color
B. coefficient of thermal expansion
C. Modulus of rupture
D. Young’s modulus
E. Compressive strength
807. The strongest phase in dental amalgam is?
A. gamma
B. beta 1
C. gamma 1
D. alpha 2
E. gamma 2
808. The primary corrosion products of amalgam are?
A. silver chloride or fluoride
B. copper sulfates
C. oxides and chlorides of tin
D. zinc and silver dioxide
809. Zinc oxide eugenol pastes should not be used as?
A. a surgical dressing
B. a permanent filling material
C. a bite registration paste
D. a temporary relining material for dentures
E. an impression material
810. Creep is associated with?
A. flow of molten alloy along the sprue
B. contact angle measurement
C. slumpoccurring in porcelain glasses
D. marginal breakdown of amalgam
E. expansion of the investment mold