The principal raw materials for the manufacture of urea are
A.CO2 and NH3
B.CO2 and HNO3
C.CO and NH3
D.CO2 and N2
A.CO2 and NH3
B.CO2 and HNO3
C.CO and NH3
D.CO2 and N2
A.Zinc sulphate
B.Magnesium sulphate
C.Sodium sulphate
D.Copper sulphate
A.38.4 wt. %
B.46 wt. %
C.59.1 wt. %
D.61.3 wt. %
A.phosphate rock is ground to -200 mesh
B.phosphate rock is ground to -150 mesh
C.phosphate rock is ground to -100 mesh
D.phosphate rock is ground to -20 mesh
A.reversible
B.endothermic
C.catalytic
D.exothermic
A.rectification with 93% HCl
B.adding 70-75% Mg (NO3)2 solution with 60% HNO3
C.distilling at 1 atm
D.all of the above
A.finely divided iron is used as a catalyst
B.finely divided molybdenum is used as a catalyst
C.finely divided nickel is used as a catalyst
D.no catalyst is required
A.calcium phosphate
B.crude phosphorus
C.animal charcoal
D.ammonium phosphate
A.phosphorus oxychloride
B.phosphorus trichloride
C.orthophosphoric acid
D.phosphorus pentoxide