211. The solvent flux used for base metal soldering is_______________?
A. Boric acid
212. During soldering, the solidus temperature of the filler material should be_____________?
A. Greater than the substrate material
B. Lesser than the substrate material
C. Equal to the substrate material
D. Temperature not relevant
213. Which of the following increases castability of base metal alloys________________?
214. Which of the following fuel gases used for soldering, has the highest heat content______________?
B. Natural gas
215. Binder in phosphate bonded investment is______________?
A. Magnesium oxide & Phosphate
B. Magnesium oxide & Phosphoric acid
C. Magnesium oxide & Monoammonium phosphate
D. Magnesium oxide & Ortho Phosphoric acid
216. Which one of the following elements is NOT added is small amount to be used as grain refiners ?
217. Within an hour after cementation of cast gold onlay patient complains of shooting pain every time the teeth comes together Most probable explanation is ______________?
A. Supracocclusion of restoration
B. Retained cement in gingival sulcus
C. Excess acid in mix
D. Galvanic current caused by gold onlay occluding with a large restoration
218. The rate of tarnish and corrosion of class II cast material having VHN 200 is_______________?
B. 2 to 3%
C. 5 to 10%
219. Function of wetting agents used in casting procedure is_________________?
A. To felicitate wetting of ring liner
B. To felicitate mixing investment
C. To reduce contact angle of liquid with max surface
D. For better wax elimination
220. The deoxidizing agent added to dental alloys is______________?