Fusion zone in the electric furnace used for reduction of phosphate rock to elemental phosphorous is maintained at ______________ °C?

Related Mcqs:

1. Yield of elemental phosphorous from rock phosphate is about _____________ percent?

   A. 1-2
   B. 15-25
   C. 40-45
   D. 60-65

2. A mixture of phosphate rock ______________ is heated in an electric furnace to produce phosphorous?

   A. Salt & coke
   B. Sand & coke
   C. And coke
   D. And sand

3. Electric furnace method for production of phosphorous uses phosphate rock and _________________________?

   A. Phosphoric acid
   B. Coke
   C. Sulphuric acid
   D. Silica and coke

4. Heating of coke, sand & phosphate rock in an electric furnace is done for the manufacture of_________________?

   A. Phosphoric acid
   B. Superphosphate
   C. Phosphorous
   D. Triple superphosphate

5. Heating a mixture of phosphate rock, coke and sand in an electric furnace produces___________________?

   A. Phosphoric acid
   B. Ammonium phosphate
   C. Phosphorous
   D. Superphosphate

6. Low grade phosphate rock can be used in electrical furnace, because__________________?

   A. Of the better CaO/SiO2 balance for slag formation
   B. CaO content is less
   C. It is cheap
   D. It produces low cost product

7. Conversion of yellow phosphorous to red phosphorous is done by heating it in covered retorts at ____________ °C in absence of air?

   A. 50-80
   B. 250-400
   C. 1000-1200
   D. 800-900

8. Red phosphorous is changed into white phosphorous by______________________?

   A. Heating in presence of light
   B. Melting under pressure
   C. Vaporisation followed by condensation
   D. None of these

9. Reaction of ______________ acid with phosphate rock produces superphosphates?

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

10. Phosphoric acid is produced in wet process from phosphate rock and____________________?

    A. Dilute H2SO4
    B. Concentrated H2SO4
    C. Concentrated NHO3
    D. Concentrated HCl