A. Excess liquid ammonia and liquefied CO2
B. Excess liquid ammonia and compressed CO2 gas
C. Liquid ammonia and excess compressed CO2
D. Compressed ammonia gas and excess compressed CO2
Related Mcqs:
- Temperature and pressure in urea autoclave is_________________?
A. 120°C and 300 atm
B. 190°C and 200 atm
C. 400°C and 550 atm
D. 200°C and 10 atm - Prilling of urea should be accomplished (in a sprayer) just above the melting point of urea with minimum of retention time, otherwise it will result in__________________?
A. Low bulk density product
B. Biuret formation
C. Non-spherical prills
D. Substantially wet non-flowing and sticky product - Yield of urea can be increased with excess ammonia and higher pressure & temperature, but because of ____________ this is normally not done?
A. Increased biuret formation
B. High corrosion rate
C. Increased cost of equipment
D. All A., B. & C. - Lower temperature and large excess of ammonia in urea melt__________________?
A. Increases biuret formation
B. Decreases biuret formation
C. Is undesirable
D. Does not effect biuret formation - Though kinetics of ammonia synthesis dictates the use of low temperature for high equilibrium conversion, yet it is kept moderately high (550°C), because at low temperature___________________?
A. Rate of reaction is very low
B. Very high pressure is required resulting in costly pressure vessel
C. Space velocity of gas is very low resulting in decreased conversion
D. None of these - ____________ catalyst is used in the production of urea from CO2 and NH3?
A. Vanadium pentoxide
B. No
C. Alumina
D. Nickel - An increase in the NH3/CO2 ratio in urea manufacture results in__________________?
A. Increased degree of conversion of CO2 to urea
B. Decreased degree of conversion of NH3 to urea
C. Decreased yield of urea
D. Decreased specific volume of molten mass - Dehydration of ammonium carbamate (to produce urea) is a/an _____________ reaction?
A. Reversible
B. Catalytic
C. Exothermic
D. Endothermic - Urea is represented as______________________?
A. NH2.CO.NH2
B. NH3CO.CH3
C. NH.CO2.NH
D. NH3.CO2.NH3 - _____________ is the undesirable by-product produced in the manufacture of urea ?
A. Ammonium carbonate
B. Biuret
C. Carbon dioxide
D. Ammonium carbamate
