The strength of a gypsum investment is dependent on_______________?

Related Mcqs:

1. The product, which is obtained by calcining gypsum under steam pressure at 120-130°C or by dehydrating gypsum in the presence of sodium succinate is_______________?

   A. Alpha – hemihydrates
   B. Beta – hemihydrates
   C. Calcium sulphate dihydrate
   D. Orthorhombic anhydrate

2. Gypsum bonded investment should not be heated over______________?

   A. 700°C
   B. 1,300°C
   C. 1,063°C
   D. 900°C

3. Quartz is added to gypsum bonded investment to______________?

   A. Increase the strength
   B. Counter balance contraction of gypsum during heating
   C. aid in hygroscopic expansion
   D. Increase the shelf life of investment

4. Binder used in Gypsum investment is_________________?

   A. Silica
   B. Quartz
   C. Cristobolite
   D. Calcium sulphate monohydrate

5. The best pickling solution for gypsum bonded investment is_______________?

   A. Hydrochloric acid
   B. Nitric acid
   C. Sulphuric acid
   D. Phosphoric acid

6. A thinner mix of a gypsum bonded investment will_______________?

   A. Produce a smoother casting
   B. Decrease setting expansion
   C. Increase setting expansion
   D. Increase thermal expansion

7. The strength of gypsum prouducts is generally expressed in terms of______________?

   A. Tensile strength
   B. Wet strength
   C. Green strength
   D. compressive strength

8. The strength of the gypsum specimen when the water in excess of that required for the hydrate of the hemihydrate is left in the specimen is called____________?

   A. Dry strength
   B. Green strength
   C. Water strength
   D. Compressive strength

9. Materials which has high compressive strength and low tensile strength is classified with property of________________?

   A. Ductility
   B. Brittleness
   C. Malleability
   D. Resilient

10. ADA specification number of gypsum products are described under____________?

    A. 1
    B. 4
    C. 12
    D. 25