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The correct choice is (d) None of the mentioned

Explanation: The purification of the crude product is ACCOMPLISHED also by RECRYSTALLIZATION. The SUCCESS of the purification depends upon certain details of manipulator which include (1) USE of a minimum of SOLVENT and (2) constant agitation while recrystallization takes place in order to assure the formation of crystals.

The correct choice is (a) NITROTOLUENES

To explain I WOULD SAY: The nitrotoluenes are used primarily as intermediates in the dye industry and the TOLUENE diamines derived from dinitrotoluenes are used as intermediates for the PRODUCTION of isocyanates.

Right choice is (a) (1,3)-Dinitrobenzene

To explain: ‘m’ stands for ‘meta’, and it’s position is 3rd Carbon on the BENZENE ring, whereas 2 and 4 are ortho and PARA respectively.

Correct choice is (c) All of the mentioned

To explain I would SAY: In LOSS in Wash WATERS,the losses INCIDENTAL to the neutralization of the NITROBENZENE are directly proportional to the number of washes given and the amount of water used.

The correct option is (a) Tends to complete nitration and esterification reaction

Easiest EXPLANATION: Since increasing D.V.S. tends to drive the nitration or esterification FARTHER toward COMPLETION, whereas lower D.V.S. would permit accumulation of incompletely nitrated MATERIAL, along with increased dilution, and this would be favourable to oxidation reactions.

Right option is (b) DECREASE in stability

The best I can explain: It is FOUND experimentally that increasing D.V.S. favours high stability of the nitrator charge, while DECREASING the D.V.S results in LOWERING stability.

The correct OPTION is (d) All of the mentioned

The EXPLANATION is: The FORMULA for NITRIC acid (R) is R= N/X which can be rearranged to get the other FORMULAE.

Correct OPTION is (d) S / (EN / R+W)

To explain: For calculating the DVS Value the following formula is used : S / (EN / R+W) ,Where: S = percent actual H2SO4,

N = PER CENT actual HNO3

W = per cent WATER

E = water equivalent of material to be nitrated and

R = nitric ratio.

Correct ANSWER is (c) Both of the mentioned

The EXPLANATION is: The NO2+ is called nitrly or NITRONIUM ion, it is called an ion because it CONTAINS a charge on it.

Correct answer is (a) RATIO of wt of 100% HNO3 / wt of MATERIALS being nitrated

Explanation: Nitric ratio is denoted by ‘R’ and it is the ratio of the weights of 100 per cent HN03 to WEIGHT of MATERIAL being nitrated.

Right option is (C) R

To EXPLAIN: Nitric RATIO is denoted by ‘R’ and it is the ratio of the WEIGHTS of 100 per cent HN03 to weight of material being nitrated.

The correct option is (d) All of the mentioned

For explanation I WOULD say: One of the REACTANT is USUALLY PRESENT in excess in order to maintain reasonably fast over-all reaction rates andto satisfy the stoichiometric REQUIREMENTS of the nitration reaction.

The correct answer is (d) All of the mentioned

Easy explanation: Agitation is needed to PROVIDE efficiency in reactor, even violent, to smooth REACTIONS and ALSO to AVOID local overheating which could OCCUR if stagnant spots were to exist in the nitrator.

Correct answer is (c) Both of the mentioned

Easy explanation: Agitation generally must be very efficient, even violent, in order to obtain smooth reactions and to avoid LOCAL overheating which could occur if stagnant spots were to exist in the nitrator and control of TEMPERATURE is ALSO important so that ACCIDENTS do not occur.

The correct answer is (d) We dump the content in a drowning tub and remove flumes through air outlet

Easy explanation: In such cases of an emergency the contents of the NITRATOR is dumped rapidly rapidly into a large VOLUME of water contained in a “drowning tub.” A common accessory for a nitrator is a suction line in the vapour SPACE above the liquid charge to remove the acid fumes and OXIDES of NITROGEN which may be liberated.

Right answer is (b) False

For explanation I would say: Since CONTINUOUS PROCESSING minimizes the amounts of material in process on the AVERAGE, it is often possible to handle OPERATIONS at one place that require physical separation in a batch process and HENCE require additional labour.

Right choice is (c) Both of the mentioned

Explanation: for nitration processing we NEED both batch and continuous PROCESS, and DEPENDING upon other requirements we CHOOSE one of these processor.

The correct ANSWER is (c) Smaller

The explanation: Since it is not necessary to accumulate material in a continuous process anywhere, the VESSELS are designed with CAPACITIES dictated by the rate of the REACTION process step which they MUST accommodate.

Correct answer is (a) True

To ELABORATE: GIVEN by Rinkenbach, the heat of nitration decreases as nitro group increases but heat of FORMATION tends to INCREASE till SECOND and third group and diminishes thereafter.

Right OPTION is (a) Batch process equipment

The BEST explanation: Because each batch of MATERIALS passing through batch process are separate and it is easier to introduce process variation in batch than in CONTINUOUS process.

The correct choice is (b) (II) a-(2,4,6) trinitrotoluene

Easiest explanation: a-(2,4,6) trinitrotoluene has the highest heat of FORMATION because it is quite STABLE without any stain within the molecules, and has LOW internal energy.

Correct option is (d) All of the mentioned

The best I can explain: HEAT of nitration or heat of reaction or heat of FORMATION ‘Q’ is an exothermic reaction, and it is the total AMOUNT of heat given out during nitration reaction.

The correct answer is (a) H

Best EXPLANATION: the enthalpy of REACTION is DENOTED by H.

The correct choice is (a) True

To explain: As a huge AMOUNT of HEAT is LIBERATED during nitration reaction therefore it is called EXOTHERMIC, if heat was to be added it would be called endothermic reaction.

The correct OPTION is (d) It’s a REVERSIBLE process

Easy explanation: Nitrate ester is a reversible process whereas nitration to FORM NITRO compounds is not.

The correct option is (b) False

To explain: Because of their sensitivity toward ACID, they probably do not SURVIVE in the strongly acidic ENVIRONMENT of the nitration.

Right option is (c) RCO-N(-NO2)-R’

For EXPLANATION: The following compound is called nitro amides because ‘-CO’ is DIRECTLY attached to ‘-N’ group.

Correct CHOICE is (d) All of the mentioned

Explanation: All of these COMPOUNDS have an -OH group attached to it.

Right answer is (d) All of the mentioned

To explain I would say: It is EASIER for the reaction in gas PHASE than in LIQUID phase DUE to the above reasons.

The CORRECT answer is (d) All of the mentioned

Easiest explanation: ALKYL mean atom or molecule containing a ‘C’ atom, which all the above contains and radical which can easily react with other molecule as it has a VACANT spot.

The correct ANSWER is (a) True

Best explanation: The rate of SUBSTITUTION in the REVERSE order at low temperature. As the REACTION temperature is increased, the rates tend to approach equality.

The correct choice is (a) Positive

To explain: Bromine has a beneficial EFFECT on YIELD and conversion of Nitric acid to Nitroparaffins, similarly CHLORINE ALSO effects the yield.

Correct answer is (C) Temperature at which we GET MAXIMUM yield

The best I can explain: Optimum temperature is a temperature at which we get maximum yield i.e maximum about of desired product.

The correct choice is (C) Free radical

For EXPLANATION: The PARAFFINIC are susceptible i.e. inert to the attack of electro or nucleophile whereas they are affected by certain atoms or free RADICALS.

Correct option is (d) Three

The best I can explain: Picric acid is also called 2, 4, 6- TRINITROPHENOL and hence it contains three nitro GROUPS.

Right answer is (a) Mononitroparaffins

For EXPLANATION I would say: The nitration PROCESS cannot PRODUCE any polynitro compounds HENCE we only get Mononitration PARAFFIN’s.

Right answer is (a) True

Easy explanation: Nitrosyl ION in NO+ WHEREAS Nitrile ion in NO-, THEREFORE nitrite ion is a STRONGER electrophile.

Correct choice is (d) All of the mentioned

The explanation: RDS is called the rate DETERMINING STEP, the rate of REACTION depends on this step and the majority of reaction takes place through this step.