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Right CHOICE is (a) True

Easy explanation: Catalysts are generally used in an effort to obtain the oxidation REACTION at as Iowa temperature as POSSIBLE and to direct the reaction, to the desired PRODUCTS.

The correct option is (c) CADMIUM

To elaborate: The BOILING point of the MERCURY can be altered by introducing alloying metals such as cadmium.

Correct CHOICE is (b) Control the temperature

For EXPLANATION: By varying the pressure on the two-phase mercury system, it is possible to control the temperature of the liquid bath and of the catalyst MASS. This may be ACCOMPLISHED by the use of NITROGEN pressure.

Correct ANSWER is (a) True

Easy explanation: Mercury has both advantages and disadvantages for use as the heat removing fluid. Its boiling point of 357°C at atmospheric pressure may be easily raised to 400-450°C by the application of nitrogen pressure. It is fluid at room temperature and introduces no hazard of equipment damage due to solidification through ACCIDENTAL cooling because of SHUTDOWN of equipment. Mercury VAPOUR is toxic; the liquid is HEAVY; and leaks in the pressure system are difficult to prevent.

Correct answer is (a) REMOVES HEAT

Explanation: The mercury (liquid and vapour) is the means for removing the heat of a REACTION at a constant temperature of about 425°C and for dissipating it to COOLING water at a temperature of about 100°C.

Correct OPTION is (c) Removes heat

The best EXPLANATION: The liquid bath MAY be used to remove heat from the reaction as latent heat of evaporation of the liquid.

The correct choice is (b) PREVENT destruction

The explanation: Removal of heat is essential to prevent destruction of apparatus, catalyst, or raw MATERIAL, and maintenance of TEMPERATURE at the PROPER LEVEL is necessary to ensure the correct rate and degree of oxidation.

Right OPTION is (c) Below 500

To explain: Noncatalytic OXIDATION of the AROMATIC HYDROCARBONS is slow at temperatures below 500°C.

The correct choice is (b) Yes

Best explanation: By conducting the oxidation of the LOW-molecular-weight paraffin hydrocarbons under high pressures it has been possible to obtain alcohols, increased YIELDS of aldehydes, and acids as oxidation products. Conditions claimed for the pressure processes include (1) pressures of 50-250 ATM, (2) temperatures from 200-600°C, (3) low oxygen: hydrocarbon ratios ranging from 5-15 moles PER cent, (4) short time of contact, and (5) the presence.

Correct ANSWER is (d) All of the mentioned

Easiest explanation: CONTROL is effected by LIMITING the time of contact, temperature, proportion of oxygen, or type of catalyst or by COMBINATIONS of these factors.

Correct option is (d) All of the mentioned

To explain: Temperatures are low or moderate, and the extent of oxidation may be readily controlled by (1) limiting the DURATION of operation, (2) CONTROLLING the temperature, and (3) limiting the amount of OXIDIZING AGENT.

Correct option is (a) Volatile

The EXPLANATION: Vapour-phase oxidation reactions can be EFFECTIVELY APPLIED only to readily volatile substances that are of sufficient thermal stability to resist DISSOCIATION at elevated temperatures.

Right option is (a) Vapour

Best EXPLANATION: Oxidations are conducted in the liquid PHASE in cases where high-molecular-weight, complex, and more or less THERMALLY unstable substances are dealt with and where the oxidizing agent is relatively non-volatile.

The correct option is (c) Nitric oxide

The best explanation: Only two OXIDATION agents have been USED in the past for conversion of xylene ISOMERS to phthalic acids-air and nitric acid. No single process has been found completely satisfactory for use with all three isomers, and at PRESENT a different process is used for each.

The correct option is (b) Loss of products

Easy explanation: In the majority of CASES, steps must be taken to limit the EXTENT of the reaction and prevent complete loss of product through CONTINUED OXIDATION.

The correct option is (b) Endothermic

Best explanation: The dehydrogenation reaction is endothermic, and a CONSIDERABLE amount of heat has to be ADDED to the CONVERTER in order to MAINTAIN the reaction temperature.

Correct choice is (b) Styrene

Explanation: Styrene is PREPARED by dehydrogenating ETHYLBENZENE over a zinc oxide CATALYST at approximately 600°C.

The correct option is (d) All of the mentioned

The best explanation: The products of TOLUENE oxidation, chiefly benzaldehyde, benzoic acid, maleic acid, and ANTHRAQUINONE, are obtained in proportions that depend UPON catalyst, temperature, OXYGEN ratio, and time of CONTACT.

Correct CHOICE is (a) HIGH

Easy explanation: High temperatures, mild CATALYSTS, and SHORT times of contact promote the formation of BENZALDEHYDE.

Correct option is (a) True

Explanation: The oxidation of hydrocarbons having an AROMATIC nucleus and one or more SIDE chains may be effected in the side chain without marked rupture of the RING itself, since each component behaves more or less as it would if it alone constituted the major part of the molecule. Thus, the ring component exhibits the characteristic stability of the aromatic compounds.

Correct option is (a) Yes

Explanation: Continued OXIDATION of benzene leads to RUPTURE of the ring and results in the FORMATION of maleic acid, which MAY be obtained in good yields.

The correct CHOICE is (a) True

The explanation: With such relatively mild catalysts as copper oxide and glass surfaces, some HIGH yields of formaldehyde have been obtained from methane and ETHANE under experimental CONDITIONS.

Correct answer is (d) All of the mentioned

Explanation: Oxidation of natural gas with very low oxygen CONCENTRATIONS under slight pressure and in the presence of a catalyst, such as copper-copper oxide, has been shown CAPABLE of PRODUCING a useful mixture of OXYGENATED products, i.e., FORMALDEHYDE, acetaldehyde, and methanol.

Correct answer is (a) High

The best explanation: Catalytic vapour-phase oxidation of the unsaturated alcohols to form unsaturated CARBONYL COMPOUNDS has been found to give considerably HIGHER YIELDS.

The correct answer is (a) True

To explain I would say: The DIRECT oxidation of ethanol to acetic ACID in a continuous catalytic vapour-phase PROCESS is more DIFFICULT since LOSSES to formaldehyde, carbon oxides, etc., occur.

The correct answer is (d) Methyl VINYL KETONE

Best EXPLANATION: Catalytic DEHYDROGENATION of methyl vinyl carbinol at temperatures above 250°C in presence of a BRASS spelter catalyst is claimed to give a 33 per cent yield of methyl vinyl ketone, CH3-CO-CH=CH2.

Right ANSWER is (b) Endothermic

The EXPLANATION is: Oxidation of METHANOL reaction is endothermic, and HEAT must be supplied.

Right answer is (d) ACETALDEHYDE

To explain I would say: Ethanol MAY be dehydrogenated or OXIDIZED to acetaldehyde in the vapour phase with good yields.

The correct choice is (a) Carbon MONOXIDE

The EXPLANATION: During oxidation of methanol by VAPOUR phase oxidation, is GIVE carbon monoxide and hydrogen as products.

Correct choice is (d) All of the mentioned

The BEST explanation: Oxidations has centered quite LARGELY in the formation of fatty acids SUITABLE for the PRODUCTION of soaps, fats, esters, SOLVENTS, etc., or capable of hydrogenation to high-molecular-weight alcohols.

Correct OPTION is (b) False

To explain I would say: The vapour phase oxidation must have sufficiently high vapour pressures at the temperatures required for oxidation to make it possible to MIX them with AIR (oxygen) and pass them in the gaseous state over the CATALYST MATERIAL.

Correct choice is (b) CYCLOHEXANE

Easy explanation: Petroleum-derived cyclohexane is the significant commercial raw material for adipic acid manufacture, cyclohexane MAY be converted by OXIDATION to adipic acid by EITHER of two basically different PROCESSES.

The correct choice is (c) SODIUM and Lithium

The best explanation: Sodium and lithium soaps of these acids have been described as PROMISING for the MANUFACTURE of LUBRICATING greases.

Correct option is (c) Mg

Easy explanation: various liquids as solvents, preferably organic acids RELATIVELY inert to oxidation; catalysts such as SALTS of Ce, CO, Cu, Mn, V, U, Fe; plus promoters such as salts of Ba, Mg, Ki plus “initiators” such as peroxides, peracids, aldehydes, ketones, OLEFINS, or organic substances forming peroxides.

Correct OPTION is (d) All of the mentioned

For explanation: OXIDATION of fatty oils by peracetic acid results in PRODUCTS which arc epoxidized, hydroxylated, and acetylated and have properties of VALUE for USE in vinyl plasticizers and greases.

Correct option is (B) Liquid

Best explanation: Acetaldehyde to Acetic ACID, the formation of acetic acid furnishes an excellent EXAMPLE of liquid-phase oxidation with molecular oxygen.

Correct choice is (a) True

To explain I would SAY: The reduction of quinone to hydro quinone and the reoxidation of HYDROQUINONE to quinone are very RAPID PROCESSES and are STRICTLY reversible. This reaction is one of the rare oxidation and reduction reactions of organic chemistry that are rapid and reversible.

Right answer is (d) All of the mentioned

The BEST explanation: HYDROQUINONE, in turn, is READILY OXIDIZED to quinone by such agents as chlorine, nitric acid, persulfuric acid, chromic acid, FERRIC chloride, and permanganates.

Right CHOICE is (B) False

Best explanation: QUINONE is readily REDUCED to hydroquinone, and much of the quinone that is manufactured is SOLD in the form of the hydrogenated product.

The CORRECT answer is (b) KMnO4

The best I can explain: SODIUM or potassium dichromate may be used to oxidize aniline to QUINONE, but a low temperature and slow addition of the oxidizing agent must be employed in order to restrict the ACTION.

The correct option is (b) Less

Explanation: Less potent agents, such as nitrobenzene, have consequently been USED for the DIRECT oxidation of isoeugenol to vanillin. Nitrobenzene has an advantage over more powerful oxidizing agents, such as the DICHROMATES and PERMANGANATES, in the oxidation.