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Correct choice is (c) Aromatic hydrocarbon

Easiest explanation: TETRA hydro FURAN and diethyl ETHER are used to increase CONDUCTIVITY, ethyl magnesium chloride (Grignard reagent) is a raw material for production of tetra ethyl lead, and aromatic hydrocarbon is used as thermal stabilizer for TEL.

The correct ANSWER is (a) Photochemical application of ARC

The explanation: Arc image furnace is the radiation and photochemical application of high intensity arc, while mechanical application of arc is such as new design of WIND tunnels, cutting and welding of metals etc.

Correct option is (a) Electric furnacing

To explain I would say: In electric furnacing PROCESS, ALLOY steels are produced while aluminium, MAGNESIUM and sodium cells are related to FUSED electrolytic, ozone is related to GAS phase electric discharge and nickel, chrome plating on steel are done in electroplating.

The correct option is (b) Volatile cell

Explanation: Electrolysis cell USES ELECTRICAL energy to produce endothermic CHEMICAL changes, fuel cell and conventional cellsprovide endothermic change while volatile cell uses EXOTHERMIC chemical reactions to produce electrical energy.

The correct CHOICE is (a) 368

To explain: The atomic WEIGHTS of SODIUM, phosphorous, oxygen are 23, 31, and 16 respectively. Hence the TOTAL molecular weight is (23*5) + (31*3) + (16*10) = 368.

The correct choice is (d) H2SO4

The explanation: CARBO nitric process is a complex reaction involving calcium phosphate Ca3(PO4)2, AMMONIA NH3, nitric acid HNO3, carbon DIOXIDE CO2, and water.

The correct ANSWER is (c) 25-30 kg

Best EXPLANATION: In producer gas production 8-10 kg steam required, 20-25 kg COKE required, 25-30 kg COAL required and 60-80 kg air required.

Correct answer is (b) ALKALI

Easy explanation: In CONTACT process alkali is USED as promoter in trace AMOUNTS to enhance activity of catalytic AGENT in order to decrease the reaction time for better economy.

Right answer is (c) Arsenic

For explanation I would say: In the contact process arsenic usually attacks the VANADIUM catalyst. It can be removed by contacting MOLTEN sulfur with milk of lime in a continuous autoclave. Lead and ZINC usually don’t react with vanadium under the conditions provide in the contact process.

Right choice is (d) All of the mentioned

Easy explanation: The major engineering problems encountered during production of acetylene from calcium carbide are Choice of lime, Avoidance of contact of CAC2 with moisture while storage and grinding, Temperature and PRESSURE control in the GENERATORS, Waste disposal of lime RESIDUE from generator.

The correct ANSWER is (c) Operating costs

To explain: Operating costs are the costs that are involved with the operation of the plant for the production ACTIVITY, which comes under manufacturing costs. Other TERMS options mentioned Employee benefits, Cafeteria, Freight and DELIVERY doesn’t come under manufacturing costs.

Right answer is (b) HMX

Best explanation: ALTERNATE names of HMX explosives are – high MELTING explosives, cyclotetramethylenetetranitramine, OCTOGEN, high velocity MILITARY explosives and his/her majesty’s explosives.

The CORRECT answer is (c) ORGANIC phosphate

Explanation: This process is ONE of a removal of non-uranium constituents process. Solvent extraction of acid LEACH slurries is done by organic phosphate esters such as tributyl phosphate in KEROSENE.

The correct OPTION is (c) HDO

To explain I WOULD say: Deuterium exists in natural water as HDO and in hydrogen from petroleum sources as HD. The isotopic atom PERCENTAGE in both source type is 0.0143%. To produce 99+ % is a sizeable separation task.

Correct ANSWER is (a) HCl and H2SO4

To explain: By-product acids HCl and H2SO4 are USED in BROMINE production in order to acidify the incoming seawater. Bromine reacts with SO2 and water and gives H2SO4 and HBr.

The correct choice is (d) 1 day each to LOAD and UNLOAD

The best EXPLANATION: A run REQUIRES 2-4 days of heating, 1 day each to load and unload, and 15-20 days for COOLING. After every run we must rebuilt the furnace side walls.

The correct answer is (C) 1400°C

Explanation: Coke is calcined at 1400°C to evaporate IMPURITIES, mixed with pitch, made into SHAPES and SENT to graphitizing furnace where the TEMPERATURE is 3000°C.

Right option is (d) Ca(H2PO4)2

Best explanation: CaH4(PO4)2 represents super PHOSPHATE, Ca3(PO4)2 represents calcium phosphate, and CaHPO4represents bi calcium phosphate where ASCA(H2PO4)2 represents MONO calcium phosphate.

The correct answer is (d) NA5P3O10

The best I can explain: The chemical structure of poly phosphate is X5P3O10. Hence the chemical formula for SODIUM tri polyphosphate is Na5P3O10 which is formed by the combination of 1 mole of monosodium to 2 moles of disodium phosphate.

Right ANSWER is (d) Calcium PHOSPHATE production

Explanation: ‘Acidulation’ REACTION is ASSOCIATED with calcium phosphate production. In this reaction phosphate rock reacts with aqueous H2SO4 and produced superphosphate and HF.

Right ANSWER is (a) amines

The best explanation: For treatment the hot ammonium NITRATE granules are coated with amines (anti-caking agent) to prevent caking and then treated with INERT material in the FINAL step. THUS, formed ammonium nitrate granules are sent for packaging.

Right answer is (a) Lower oxidation YIELD

For explanation I would say: Lower oxidation yield is one of the major disadvantages of USING high pressure while OTHERS higher acid strength, high reaction rates are advantages of using higher PROCESS.

Right ANSWER is (c) OXIDATION of NH3 to NO2

For EXPLANATION: All the STEPS including oxidation of NH3 to NO, oxidation of NO to NO2 and absorption of NO2 in WATER are the fundamental steps for the production of nitric acid.

Correct CHOICE is (b) 1.5-2 hours

The best I can explain: The average RESIDENCE time in the AUTOCLAVE, which is OPERATED on continuous basis, is 1.5-2 hours.

The correct option is (d) All of the mentioned

Explanation: CALCIUM CARBIDE plants are ECONOMICAL at a plant location supplying cheap power, AMPLE limestone and adequate waste DISPOSAL facilities.

The correct answer is (a) First LAW

The best explanation: First law of THERMODYNAMICS is a version of Law of CONSERVATION of ENERGY, which states that Total energy given to the system is used to increase the INTERNAL energy of the system and the expansion (PV) work.

Right answer is (d) Binder

To explain I would say: Basically HTPB(Hydroxy-terminated polybutadiene) is one of a binder. Binders are COMPOSITION that hold TOGETHER a CHARGE of finely divided particles and increased mechanical strength of the RESULTING PROPELLANT hrain.

Right choice is (a) TEMPERATURE sensitivity

Best explanation: The burning rate in solid propellants is dependent UPON the prior storage temperature. This temperature sensitivity is a MAJOR DISADVANTAGE of solid propellants when compared with liquid propellants.

Correct OPTION is (a) Steel

The explanation: The largest users of water industry are-steel, oil refineries, PULP and paper. In processing, water is entering into or contacting MANUFACTURED products. Power generations, surface condensers and FEED water.

Right answer is (b) FALSE

For explanation: The statement is false since sodium hydroxide is HIGHLY soluble in water with high heat of SOLUTION (exothermic). It is insoluble in ETHER and other non-polar SOLVENTS.

Correct option is (a) \(\frac{(EIT)}{∆H} \)

Explanation: The overall efficiency of a FUEL cell is given by \(ƞ_o=\frac{EIT}{∆H}.\) It is the fraction of HEAT reaction of PRIMARY fuel converted into useful electric work at the device terminals.

The correct option is (a) 25-40%

To explain: The STRENGTH of NITRIC acid USED is 25-40% and the chemical reaction is completed in the ammoniating TANK to which the digested slurry is pumped.

Correct answer is (a) H2SO4

For explanation I WOULD SAY: Superphosphate grade of calcium phosphate is PRODUCED by the reaction of phosphate rock with sulfuric acid, H2SO4.

Correct choice is (C) 1.67

To explain I would say: Soda ash solution and concentrated H3PO4 are diluted in a batch mixing TANK. A 1.67 RATIO ofNa2O/P2O5 is required to form of 1 mole of monosodium to 2 moles of DISODIUM PHOSPHATE.

The correct choice is (d) Rubber lined steel

Best explanation: Reaction tanks are made of Steel lined with acid PROOF BRICK. Filter is type 316 stainless steel. Storage tanks are made up of rubber lined steel. AIR vent systems are made up of PVC coated steel.

The correct OPTION is (b) Calcium CARBONATE PRODUCTION

To elaborate: In phosphoric acid production, GYPSUM is formed as intermediate and it can be REACTED with ammonium carbonates to give ammonium sulphate (fertilizer ingredient) and calcium carbonate (merseberg process).

The correct option is (C) H2O and CO2

Explanation: AIR CONTAINING both H2O and CO2 which must be removed before entering the FRACTIONATION column operated at -183 to -195 celsius to prevent plugging in the Linde- Frankl cycle.

Right OPTION is (a) Prilled

To EXPLAIN I WOULD say: Ammonium nitrate is formed into droplets by prilling. Although granulation is preferred from environmental POINT of VIEW granulation is not usually done because it requires a more complex setup and a variety of equipment.

The CORRECT option is (c) H2

For explanation: From the petroleum refinery catalytic reforming PROCESS H2 can be OBTAINED as by-product which is being used for captive ammonia SYNTHESIS at refinery location.

Right choice is (a) CO and H2

For explanation: SYNTHESIS gas is GENERALLY CONSIDERED to be a variable mixture of CO and H2 for synthesis of ORGANIC compounds. Mixture of H2 and N2 are for the ammonia synthesis and only H2 is for hydrogenation of coal.