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The CORRECT choice is (c) Uniform REACTION & High PRODUCTION RATE

To EXPLAIN: The most important advantages of continuous hydrolysis are the ability to maintain a high production rate and the uniform control of quality.

Right option is (C) Increases acid CONCENTRATION

The explanation: In hydrolysis of Starch to Sirup and Dextrose, the reaction is ACCELERATED by INCREASED TEMPERATURE and by increased acid concentration (lower pH).

The correct CHOICE is (b) DEXTROSE

Easiest explanation: A commercial CONTINUOUS converter installation for dextrose manufacture employing a continuous, automatically controlled STEP for the HYDROLYSIS of starch.

Right answer is (b) False

The best I can EXPLAIN: Such so-called “CRUDE” sugars are not generally used directly for edible purposes but find utility as fermentation substrates, as a BASE for the manufacture of caramel colour, in the finishing of leather, and in the manufacture of viscose RAYON.

The correct choice is (d) All of the mentioned

For explanation: The cost of raw material is the sum of six items: (1) cost at point of PRODUCTION, (2) cost of collection, (3) cost of transportation, (4) cost of storage to ensure year-round supply, (5) cost of PREPARATION for use, (6) and cost of disposing of by-products.

The correct option is (b) In hydrolysis of pentose

To explain I WOULD say: The chief CARBOHYDRATES are the sugars, cellulose, and starch with its related POLYSACCHARIDES. Of these, the only ones hydrolysed in large-scale industrial operations are the pentoses, from which furfural is obtained, and starch, from which glucose is PRODUCED.

Correct answer is (b) Two

Explanation: In FATTY acids, since oil or liquefied fat is INSOLUBLE in water, two liquid phases exist during hydrolysis, and the reaction rate, of course, depends upon their surface of contact–the GREATER the surface, the FASTER the SAPONIFICATION.

Right answer is (C) ALKALINE processes

The explanation is: Alkaline processes have, in general, the great advantage that, with rare exceptions, and they may be CARRIED out in iron or steel VESSELS.

Correct option is (B) Hydrolyser

To explain I would say: Hydrochloric acid as a hydrolyser and as a product of hydrolysis in the ABSENCE of alkali has been the source of MUCH trouble as it is one of the most corrosive CHEMICALS known.

The correct ANSWER is (a) True

Explanation: The DIFFICULTY of handling WET HYDROCHLORIC acid gas has been one of the retarding factors in the development of vapour-phase hydrolysis of organic halides, but the use of tantalum is finding favour in continuous processes involving large production.

The correct answer is (d) All of the mentioned

The best I can explain: Nickel and Monel metal are fairly resistant to low hydrochloric acid CONCENTRATIONS. With dilute acid, SEVERAL of the copper-base alloys, such as PHOSPHOR BRONZE, aluminium bronze, manganese bronze, and Everdur metal, have fairly good resistance and can OFTEN be used in applications where corrosion can be offset by a heavy wall thickness.

Correct choice is (d) All the mentioned

Explanation: Many non-metallic materials of CONSTRUCTION, such as rubber, stoneware, fused silica, glass, and plastic materials such as Tygon and PROFLEX, have EXCELLENT resistance to hydrochloric ACID.

The CORRECT OPTION is (B) Sulphuric acid

Easy EXPLANATION: Only two acids-sulfuric and hydrochloric-require serious consideration under acid hydrolysis.

The correct choice is (a) HYDROXYL ion

Easiest explanation: Extensive STUDY of the hydrolysis of esters has SHOWN that the reaction is REVERSIBLE and is catalyzed by both oxonium (H3O+) and hydroxyl (OH-) ions.

The correct option is (d) All of the mentioned

To explain I would say: The transition-STATE THEORY, places emphasis on the free energy of ACTIVATION and is CONCERNED with the thermodynamic probability of attaining an “ACTIVATED complex,” or transition state.

Right option is (d) FREQUENCY of collision

The best I can explain: In ARRHENIUS equation, E is the energy of activation, R the gas CONSTANT, Z the frequency of collision at unit CONCENTRATION of reactants, and P a probability FACTOR.

Correct option is (a) REVERSIBLE

Easy explanation: In inversion of Sucrose, many hydrolytic reactions, INCLUDING the decomposition of esters, are reversible; but others such as sucrose inversion and protein hydrolysis, THOUGH not NECESSARILY complete, have not been reversed.

The correct CHOICE is (a) Endothermic

The best I can explain: Hydrolysis of ALKYL Chlorides, here an estimation of the change in heat content (ENTHALPY) from bond ENERGIES SHOWS this hydrolysis to be endothermic.

The CORRECT OPTION is (b) False

The BEST explanation: HYDROLYSIS of Ethyl ACETATE is a reversible esterification reaction.

The correct choice is (B) Negative

To elaborate: If the free energy change is negative the reaction is spontaneous and BECOMES more favourable with INCREASING (-dF); on the other HAND if the free energy change is positive and greater than 10 kg-cal per mole the reaction is not SUITABLE for practical application.

The correct option is (C) Free energy

The explanation: The DRIVING force of the reaction is the CHANGE in free energy, which is related to the equilibrium constant (K).

Right ANSWER is (a) Extent of REACTION

Easiest explanation: The extent to which a chemical reaction MAY proceed under a GIVEN set of conditions is given by the equilibrium state.

Correct OPTION is (c) Botharomatic and ALIPHATIC

To EXPLAIN I would SAY: Aliphatic and aromatic amines-ethylamine and aniline-resist hydrolysis even under extreme conditions, THOUGH the production of a-naphthol from a-naphthyl amine under pressure is recorded.

Right option is (b) False

For explanation: The aromatic halides are MUCH more difficult to HYDROLYSE, ACIDS on the other HAND are EASY to hydrolyse.

Right CHOICE is (a) Acid halides

Easiest EXPLANATION: The acid halides, like acetyl chloride, REACTING readily with water alone, whereas VARYING degrees of resistance are SHOWN by the alkyl and aryl compounds.

The CORRECT OPTION is (d) All of the mentioned

For explanation: The esters of inorganic acids, ethyl and methyl sulphates, ethyl hydrogen: sulphate, the ALKYL phosphates, GLYCERYL nitrate, etc., MAY all be hydrolysed, generally speaking, by acids and bases.

Correct answer is (b) False

Explanation: Hydrolysis of esters is REVERSIBLE, unlike that of the carbohydrates, so that the EQUILIBRIUM POINT MAY be approached from both sides.

Right answer is (d) All of the mentioned

Easy explanation: Organic esters of all KINDS, including the esters of CARBOHYDRATES, are quite subject to hydrolysis with acids, bases, and, in MANY cases, ENZYMES.

The correct answer is (c) Both glucose and MALTOSE

For EXPLANATION I would SAY: Enzymes and dilute ACIDS hydrolyse starch ii1to maltose and glucose, whereas inulin YIELDS only fructose by this treatment.

The correct choice is (C) Glucose

To ELABORATE: CELLULOSE is hydrolysed to glucose by acids and to cellobiose by its own specific enzyme cellulase.

The correct option is (a) ACETALDEHYDE

The BEST I can EXPLAIN: The ADDITION of water to acetylene produces acetaldehyde.

Correct option is (b) HYDRONIUM ion

Explanation: The USE of low concentrations of alkali in the hydrolysis of esters and similar materials: Here the hydroxyl ion is supposed to catalyse the reaction as the hydrogen ion does in CATALYSIS by dilute ACID.

Correct option is (c) Invertase

The best explanation: Molasses is converted by invertase in the manufacture of industrial alcohol, and, of course, the WHOLE brewing industry depends UPON the complex hydrolysis of STARCH into maltose and GLUCOSE by the AMYLASES.

Right option is (d) All of the mentioned

Explanation: The action of acid on acetoacetic ESTER and its derivatives LEADS to acetone, CARBONIC acid, and ALCOHOL and its related products, while alkali on the same ester produces acetic acid and alcohol.

Correct choice is (b) LOWER solubility

To elaborate: Benzoyl chloride, however, reacts with LESS readiness than ACETYL chloride, despite the greater strength (dissociation) of BENZOIC acid. This is probably DUE to the lower solubility of benzoyl chloride in water.

Correct option is (d) Acetyl CHLORIDE

To explain I would SAY: Here acetyl chloride is more reactive than acetic anhydride, acetyl chloride is more readily hydrolysed than butyryl bromide. Benzoyl chloride, however, REACTS with less readiness than acetyl chloride, despite the greater STRENGTH (dissociation) of benzoic ACID.

Right option is (c) Vigorous hydrolysis

To ELABORATE: Mixed anhydrides, among which, for convenience, are included the acid halides, react with vigour, especially ACETYL CHLORIDE, which is more reactive than acetic ANHYDRIDE itself. In general, the stronger the two acids in these mixed anhydrides, the more vigorous the hydrolysis.

The correct answer is (a) Acid anhydrides

For explanation: The acid anhydrides, lactones, lactides, and other internal anhydrides such as ETHYLENE oxide are readily hydrolysed by water ALONE, acetic ANHYDRIDE reacting much more rapidly than either BENZOIC or PHTHALIC.

The correct option is (a) True

For explanation: The Grignard reagent, so USEFUL in synthesis, is hydrolysed quickly and COMPLETELY by water, as are the less manageable zinc alkyls and other organometallic COMPOUNDS.

The correct OPTION is (c) Both HIGH temperature and pressure

For explanation: ALTHOUGH the word HYDROLYSIS means decomposition by water, cases in which water unaided brings about effective hydrolysis are rare, and high temperatures and pressures are USUALLY necessary even then.

Right option is (b) False

Best explanation: HYDROLYSIS INVOLVES both OXIDATION and reduction.