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Correct CHOICE is (a) 119.5

To explain: MOLECULAR FORMULA of chloroform isCHCl3. It has 1 Carbon ATOM, 1 hydrogen atom, and 3 chlorine atoms; hence the molecular WEIGHT of methanol is 1*12+1*1+3*35.5=119.5.

Correct OPTION is (a) REFRIGERATED brine

The explanation: Refrigerated brine is used to control the TEMPERATURE in the absorber. Jacketed ARRANGEMENT is used in order to CIRCULATE the refrigerated brine in the cooling jacket. Brine is used since it has an ability to reach low temperatures without freezing problem.

The correct choice is (d) Odorants

The best explanation: Generally Mercaptans are used in odorants and soil fumigants. CARBON disulfide is used in cellophane. METHYLENE CHLORIDE is used in PAINT stripper and Freon’s.

The correct option is (c) ACETIC ACID

Easiest explanation: Some of the primary chemicals are ALCOHOL, Benzene, TOLUENE, and Acetone. Acetic acid is secondary chemical FORMED using acetylene from calcium carbide.

Right choice is (a) Adding SULFURIC acid

For explanation: The CHLORAL or CHLOROBENZENE are condensed using strong sulfuric acid or oleum as catalyst. The reaction takes place at 15°C and reaction TIME of 5-6 HOURS.

Correct option is (a) Dimerization-ISOMERIZATION-Pyrolysis

To explain: Initially propylene is dimerized USING tripropyl aluminium as CATALYST which forms 2-methyl-1-pentene which further on isomerization forms 2-methyl-2-pentene and finally UNDERGOES pyrolysis to form ISOPRENE.

The correct choice is (d) HYDRATION of ethylene

Easy explanation: Hydration of ethylene is the most economical PROCESS as ethylene is cheaper than ACETYLENE. Hence ACETALDEHYDE is produced from ethylene and water using cupric chloride as catalyst.

Correct choice is (c) Saturated carboxylic cyanohydrin

To explain I would say: Impurities in the final ACRYLONITRILE COLUMN which give TROUBLE are saturated carboxylic cyanohydrins (HO-R-CN). These dissociate to form VOLATILE contaminants.

The CORRECT CHOICE is (C) Acetonitrile and hydrogen cyanide

The best explanation: Hydrogen cyanide and acetonitrile are produced in the product stripper reactor which further goes into a purifying column. For one ton as BASIS AROUND 0.09 and 0.08 tons of acetonitrile and hydrogen cyanide is produced respectively.

The correct ANSWER is (d) H3PO4

The EXPLANATION: H3PO4 catalyst is USED in the PACKED stage reactor column for the manufacture of cumene. The reactor is packed stage WISE with H3PO4 impregnated catalyst. The catalyst maintains the temperature of the reaction to about 250°C.

Correct choice is (a) Hydration of propylene

Explanation: ISOPROPANOL is manufactured by the hydrolysis of propylene. Propylene is absorbed in a tray tower FILLED with sulfuric acid to produce ISOPROPYL acid sulphate. Ethanol is manufactured by fermentation of molasses. Oxygen is manufactured by Linde’s process whereas sulfuric acid is manufactured by CONTACT process.

Correct answer is (a) Hexa chlor yields are high at LOW contact time

To elaborate: When the contact time is low, hexa chlor yields are high and when contact time is large, destructive formation of light ENDS and carbon takes place in pyrolysis FURNACE DESIGN.

Right option is (d) Hexa CHLORO ethane

To elaborate: Hexa chloro ethane is ONE of the PYROLYSIS products of carbon TETRA chloride. The other products are per chloro ETHYLENE and chlorine with some unreacted carbon tetra chloride.

Correct option is (b) By UV light

To elaborate: The CRUX of the process involves the use of a source of free RADICALS such as ultraviolet light to produce an addition CHLORINATION REACTION.

Correct answer is (b) Caustic WASH

The explanation is: The ISOPROPANOL VAPOURS consists acidic impurities which can be removed with the help of a caustic wash tower. Caustic wash generally consists of caustic soda. Sulphuric acid is used as an ABSORBER in hydration of PROPYLENE.

Correct choice is (a) 32

To explain I would SAY: Molecular formula of methane is CH3OH. It has 3 Carbon atoms, 4 hydrogen atoms, and 1 oxygen atom; hence the molecular weight of methanol is 12*1+4*1+16*1=32.

Right ANSWER is (a) C9H12

To EXPLAIN: C9H12 is the molecular formula of CUMENE. C3H8O is the molecular formula of isopropanol. CH3COOH is the molecular formula of ACETIC acid, whereas CH3CH2COOH is the molecular formula of propanoic acid.

Correct option is (d) Tri-chlor

For explanation I WOULD say: Acid free grade of tri CHLORO ethylene is known as tri-chlor whereas HIGH purity grade is called technical grade and non-acid grade is called EXTRACTION grade, industrial grade is not present.

The CORRECT choice is (b) Ferric CHLORIDE

To explain I would say: Ferric chloride is used as catalyst in the reaction of acetylene and chlorine to GIVE tetra CHLORO ETHANE whereas barium chloride is used as catalyst in the reaction to produce tri chloro ethylene from tetra chloro ethane.

The correct choice is (b) False

Best explanation: Tri chloro ethylene is not highly soluble but slightly soluble in water. It is miscible with ethers and alcohols. It is available in DIFFERENT grades like technical, EXTRACTION ETC.

Right choice is (a) True

The BEST I can explain: The statement is true because basing on product ratio DESIRED, the methane/chlorine ratio is fixed. For feed ratio of 1.8, the product compositions obtained are 60% CH3Cl, 28% CH2Cl2, 9% CHCl3, and 3% CCl4.

Correct answer is (a) True

To explain: Girbotol is a reversible process which USES aqueous solution of mono or DI or TRI ethanolamine which ACTS as an ABSORPTION medium and hence used to recover carbon dioxide.

The CORRECT choice is (c) PALLADIUM chloride

To explain I WOULD say: New oxyesterification PROCESSES has only ethylene and oxygen as reactants and react in presence of palladium chloride to produce vinyl acetate and water.

Right CHOICE is (b) Ferric CHLORIDE

To explain I would say: Catalyst USED in MANUFACTURE of ethylene dichloride from ethylene and chlorine is TRACES of ferric chloride or ethylene dibromide. These catalysts give 90-95%yield.

Right option is (d) Acetylene is more acidic than ethylene

Explanation: Ethylene is SLIGHTLY soluble in water. GLYCOL is used as antifreeze but not in paint EMULSIONS. Some of the AROMATICS are produced as by-products in the STEAM cracking of hydrocarbons. Acetylene is more acidic than ethylene due to strong overlapping between s and p orbital’s.

Correct choice is (a) True

To explain I would say: Stage WISE packed tower with propane SENSIBLE heat quench was designed, but TUBULAR reactor design provides better sensible heat. Propane ACTS as an inert component.

Correct choice is (c) Ethylene dichloride

To explain I would say: Ethylene dichloride is USED as suppressing agent in direct OXIDATION of ethylene to suppress the side reaction which produces CARBON DIOXIDE and water instead of ethylene OXIDE.

Correct OPTION is (C) \(C_2 H_2 Cl_4\, ^{\underrightarrow{BaCl_2}}\,C_2 HCl_3+ HCl \)

To explain I would say: The correct chemical equation is \(C_2 H_2 Cl_4\, ^{\underrightarrow{BaCl_2}}\,C_2 HCl_3+ HCl \) as Ferric chloride is USED as catalyst in the reaction of ACETYLENE and chlorine to give tetra chloro ETHANE whereas barium chloride is used as catalyst in the reaction to produce tri chloro ethylene from tetra chloro ethane.

The correct option is (d) 200-350atm

The BEST I can explain: High PRESSURE is required for the manufacture of methanol. Conversion cannot take place at LOW pressure as it leads to FORMATION of INTERMEDIATE compounds.

Correct choice is (C) From SYNTHESIS gas

Explanation: Methanol is manufactured from synthesis gas when it is subjected to high PRESSURE and temperature, it converts to methanol. SULFURIC acid is manufactured by contact process. PAPER pulp is manufactured by Kraft’s process.

Right answer is (b) False

Easiest EXPLANATION: The statement is wrong because, they produce SYNTHESIS gas but by catalytic REFORMING and not by steam cracking. Petrochemical starting materials are made by steam cracking from NAPHTHA and fuel oil.

Right option is (a) Ethanol+BENZENE

Explanation: The raw MATERIALS for DDT MANUFACTURE are ethanol and benzene. The ethanol can be converted to CHLORAL by oxidation to acetaldehyde followed by chlorination.

Right option is (c) Silver oxide

To explain: Silver oxide or alumina (INERT carrier) is used as CATALYST in direct oxidation of ethylene. To reduce/avoid side REACTION, suppressing AGENT is ALSO used.

The CORRECT OPTION is (b) Absorber

For explanation: Monoethanol amine is USED as a absorber for manufacture of CO2 GAS because it’s a WEAK base which can be used as a scrubber.

Correct option is (b) Lime kiln process

The best I can explain: In lime kiln process CALCIUM CARBONATE is used along with girbotol recovery. Methanol is MANUFACTURED from synthesis gas. Kraft’s process is for the manufacture of paper PULP. Ammonium carbonate is manufactured by MONTE catini process.

Right option is (c) Mixture of CO+H2

To EXPLAIN I would say: Synthesis gas is a MAINLY a mixture of Mixture of CO+H2. The name COMES from its USE as an INTERMEDIATE in creating SNG (Synthetic natural gas). Mixture of H2+CO2+CO+N2 is called as producer gas. Mixture of CH4+H2+CO is called as coal gas.

Right choice is (d) Oxidation of naphthalene

Easiest EXPLANATION: Naphthalene mixture are melted and vaporized later it undergoes conversion in a FIXED bed converter. Dehydrogenation of ethyl benzene and HYDROGENATION dehydration of acetophenone is USED for the MANUFACTURE of styrene.

Right OPTION is (C) Petroleum coke

The best explanation: Petroleum coke is a source of electrodes for aluminum electrode and it is ALSO source of CARBON for acetylene and calcium carbide. Naphtha and fuel oil, LPG, Petroleum coke are some of the principal raw materials.

The correct option is (a) TRUE

The explanation: The STATEMENT is true as both (exothermic reactions) have UNFAVORABLE equilibrium constants under normal pressure. Reactor MUST be made up of STEEL lined with copper to prevent iron carbonyl formation which poisons the catalyst.

Right option is (a) Polystyrene

The best I can explain: Polystyrene is a thermoplastic where OTHERS are FEEDSTOCK type petrochemicals. Some other THERMOPLASTICS are polypropylene, PVC, HDP, low DENSITY polyethylene etc.