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Correct answer is (a) High temperature, low pressure

The best explanation: Thermodynamically DEHYDROGENATION reactions are FAVORABLE at High temperature and low pressure. Hydro cracking and carbon deposition can occur at high temperature, hence high hydrogen PRESSURES are USED to REDUCE them.

Correct ANSWER is (a) DECREASES

Explanation: Increase in pressure during catalytic cracking process; decreases unsaturation and hence octane NUMBER decreases, which results in increase in coke PRODUCTION though reactor throughput ALSO increases.

Right answer is (d) They are low in octane number

Easiest explanation: Catalytic reformates contains no olefins, forms blending stocks, HIGH in octane number, low in S and gum content, stable, RESISTANT to oxidation, can make COLD WEATHER petrol due to its broad boiling point range.

Right option is (B) Chromium

The explanation is: Chromium doesn’t have high TOLERANCE towards S when it is reactivated with steam in catalytic cracking process. Catalyst must be selected in such a WAY that it is not POISONED by METALS.

Right choice is (a) Higher

Easy EXPLANATION: The inlet speeds of coal dust and oxygen must be higher than velocity of FLAME propagation. Then at the base of chamber ash falls into water SEAL and hot GASES ESCAPE through top of the chamber.

Right answer is (b) False

To EXPLAIN I would say: Sizing is added to reduce WATER PENETRATION whereas fillers are added to INCREASE brightness, flexibility, opacity, bulk, weight of finished product, and softness.

Right choice is (a) Bakeries

Explanation: GRAIN PROCESSING consists of three GROUPS: primary unorganized SECTOR, organized sector, cottage scale. Cottage scale INCLUDES bakeries, rice flake making units etc.

Right answer is (d) Rosin

The best I can explain: AFRICAN copal or rosin, SHELLAC, and cashew NUT shell are the natural resins in INDIA. Alkyds, Vinyl resins, SILICONE resins, phenolic resins etc are the synthetic resins.

The correct choice is (a) OIL-based paints

To explain I would say: Oil based paints doesn’t use resins. Water based paints doesn’t use OILS and depend on resins as film forming materials. Lacquers and VARNISHES use ALKYD resins, PHENOLIC etc.

Correct choice is (d) Hydrolysis tower, vacuum still, mixer, BLENDER

For EXPLANATION I would say: RAW materials are sent into hydrolysis tower where fat splitting reaction takes place, and then the CRUDE FATTY acids are passed through vacuum still and through mixer where addition of NaOH takes place, finally through blender for saponification to take place.

Correct option is (a) PETROLEUM coke

The EXPLANATION is: Petroleum coke, ONE of the residues of petroleum refinery PROCESS is used in electrodes and also used for aluminium plants. FUEL oil is a residue, Wax is a heavy distillate, and Ammonia is a by-product.

Correct option is (d) Petroleum COKE

To explain I would SAY: Floating and frothing oil, MINERAL oil, WAXES, and lubricating oil are the heavy DISTILLATES produced in petroleum refinery process where petroleum coke is a residue.

Right option is (a) n-paraffin series

Explanation: n-paraffin series comprises the largest FRACTION of petroleum CRUDE; second abundant series in crude is Naphthene series FOLLOWED by OTHERS. Naphthene series are saturated.

Right answer is (a) True

Easy explanation: The STATEMENT is true and the gas from the oven is cooled to REMOVE tars, to remove aromatics it is scrubbed with light oil, scrubbed with sulfuric acid to remove AMMONIA leaving BEHIND COAL gas.

The correct choice is (a) Titanium oxide

Best explanation: 1% solution of Titanium oxide or MOLYBDENUM oxide is used as CATALYST in HYDROGENATION of coal to IMPREGNATE the coal into REACTION zone.

Right choice is (d) BLACK LIQUOR

Best explanation: Black liquor also known as wood digestion liquor is the waste product produced. White liquor is produced in the chemical recovery of SULFATE pulp digestion liquor which is FED to the digestors.

The correct option is (b) Zinc chrome

The best I can EXPLAIN: Apart from PRIME pigments Ultramarine BLUE, Prussian blue, phthalocyanine blue, TITANIUM DIOXIDE, carbon black etc anti-corrosive pigments like zinc chrome and basic lead sulfates are developed.

Correct choice is (a) FALSE

The best I can explain: The statement is false since soaps are sodium/potassium salts of FATTY ACIDS. Hence they are FORMED from fats and alkali.

Correct answer is (b) Glycerin

To ELABORATE: Glycerin is the important byproduct of soap MANUFACTURE. The removed 15-20% glycerin is sent into triple EFFECT evaporator for the PRODUCTION of YELLOW glycerin.

Right ANSWER is (a) Increase wet ability and decrease surface tension

To explain: Cleansing agent PROVIDES hydrophilic and hydrophobic groups which are responsible for increase in WETTING ability and DECREASING the surface tension.

The correct option is (d) Adsorption – relative ADHERENCE

Easy explanation: The GENERAL driving FORCE for any unit OPERATION is concentration gradient or more precisely chemical potential. The correct option is that adsorption is BASED on relative adherence.

The correct option is (b) By feeding paste of PULVERIZED coal and heavy oil

The best I can explain: Various ways used for feeding coal to HYDROGENATION processes are i. Treating POWDERED coal by solvent extraction and then feeding ii. By feeding paste of pulverized coal and heavy oil iii. Feeding powdered coal directly with STREAM of hydrogen.

Right OPTION is (a) BETTER BLEACH ability than paper grade pulp

Easy explanation: Pulp used for cellulose preparation should have less ASH, LIGNIN, and pentosans than paper grade pulp. It must also have better bleaching ability than paper grade pulp.

Correct answer is (b) Escape velocity decreases with increase in tank size

The BEST explanation: Escape velocity = V*v/A, where A is the unused gas escape area, V is total volume; v is the volume of air PER unit volume of liquid per unit time. V VARIES as D^3, A varies as D^2. Hence escape velocity is linearly PROPORTIONAL to D, which means escape velocity increases with increase in tank size.

The correct answer is (c) Gluten

For EXPLANATION I WOULD say: STARCH suspension contains a water insoluble protein NAMELY gluten which is separated in a two stage centrifuge operation. Starch is recovered as FILTER cake.

The correct option is (b) Multiple effect evaporators

Easy explanation: Multiple effect (3-4) evaporators are used to concentrate the clarified juice obtained in extraction of SUGARCANE to produce white crystalline SUGAR and OPEN pan evaporators are used in extraction of sugarcane to produce GUR.

Right option is (c) 25% ZnO

Best explanation: A typical EXTERIOR white paint contains 15% TIO2, 25%ZnO, 50% white LEAD, and 10% pigment extender. Paint with this COMPOSITION has self cleaning feature by a process called chalking process.

Correct OPTION is (b) False

To elaborate: The statement is wrong as manufacturing of paints, varnishes, and lacquers involves only unit operations but not unit processes. Pigments and resins manufacturing involves CHEMICAL reactions, HENCE unit processes.

The CORRECT choice is (c) Non-ionic DETERGENTS

The best I can explain: Non-ionic detergents produce little foam but have excellent grease emulsification and soil REMOVAL characteristics. Detergent builders are USED for IMPROVING the characteristics of detergents.

Right ANSWER is (d) Oleum

Best EXPLANATION: Molten sodium is added slowly to coconut oil in an aliphatic SOLVENT GENERALLY Xylene or toluene with esterifying alcohol such as amyl alcohol.

The correct option is (c) R-COOH+ M-OH → R-COOM + H2O

The explanation is: Saponification is a PROCESS used for the PRODUCTION of soap. As soap is formed by CONVERSION of fat into a fatty acid on reacting with alkali, the correct REACTION is c. Fatty acid R-COOH reacts with an alkali M-OH to produce soapR-COOMand WATER H2O.

Correct choice is (c) Lubricating oil

For explanation: Petroleum refining products constitute light ends, light HEATING oil’s, INTERMEDIATE DISTILLATES, heavy distillates, Residues, and also by-products. DIESEL oils, Heavy FUEL oils, Gas oil are the intermediate distillates where Lubricating oil is a heavy distillate.

Right choice is (a) Web forming, pressing, DRYING

Explanation: Web is formed by running the water-fiber slurry onto MOVING endless wire belt cloth where water gets drained; remaining water is removed by passing through pressure and suction rolls followed by pressing, drying and FINISHING GIVES the paper (final PRODUCT).

The correct CHOICE is (a) India

The explanation is: India is the largest PRODUCER of MILK in the WORLD followed by America, BRAZIL, Pakistan, china and soon. Three major constituents of milk are fat, protein, and sugar.

Right choice is (a) PYRIDINIUM derivatives

Easy explanation: Sulfonates are examples of ANIONIC detergents, pyridinium derivatives are cationic detergents, FATTY acid amides and ALIPHATIC polyhydric ALCOHOL esters are non-ionic detergents.

Right choice is (c) Coconut oil

To explain I would say: Based on DEGREE of unsaturation, OILS are classified as drying oils and semi-drying oils. EXAMPLES of drying oils are LINSEED, soya bean, castor oil, Tung oil, and tall oil. Examples of semi-drying oils are coconut oil, tobacco seed etc.

The correct CHOICE is (a) Extraction

To EXPLAIN: Extraction is a separation technique used to SEPARATE mixture basing on RELATIVE solubility in different solvents. This technique is mostly used in lube oil manufacture.

Right choice is (a) True

The best I can explain: Live stock MEAN cattle, bullock, sheep, GOATS, pigs, and POULTRY. Sheep and goats meat is the most important domestic market even though pork products are BECOMING popular.

The correct option is (b) False

To elaborate: The statement is false as Asphaltenes are soluble in aromatics. They are BROWNISH BLACK solids CHEMICALLY composed of carbon, hydrogen along with SULFUR, oxygen, and nitrogen.

The correct answer is (d) Dairy products

Easy explanation: MAJOR SEGMENTS of industry are consumer FOOD industry, grain processing, dairy products, fruit and vegetable processing, poultry and meat products, MARINE products. Hence consumer food industry doesn’t include dairy products.

Correct answer is (c) Poly VINYL acetate

To elaborate: Poly vinyl acetate FRAMES in LARGE number constructed in FILTER press style are used in electrolysis unit and all PIPING is coated with poly vinyl acetate to avoid corrosion.

The correct ANSWER is (b) False

Easiest explanation: The statement is WRONG as SUCROSE is highly soluble in WATER and slightly soluble in ethyl alcohol and methyl alcohol. It exists in both powered and granulated forms.

The CORRECT ANSWER is (a) Water-based paints

The explanation: Evaporation and agglomeration are modes of drying of ware-based paints. OXIDATION and polymerization are modes of drying of oil-based paints and VARNISHES. LACQUERS mode of drying is evaporation.

The CORRECT choice is (a) True

The best I can explain: The statement is true as oils are used as CARRIERS for pigments and as formers of the protective films. Hence they serve a dual purpose in surface COATING formulation.