Description : For C.I. engines fuel most preferred are a) aromatics b) paraffins c) olefins d) napthenes
Last Answer : Answer: b Explanation: For C.I. engines fuel most preferred are paraffins and for S.I. engines fuel most preferred are aromatics.
Description : In a SI engine, which one of the following is the correct order of the fuels with increasing detonation tendency? (a) Paraffins, olefins, naphthenes, aromatics (b) Aromatics, naphthenes, paraffins, olefins (c) Naphthenes, olefins, aromatics, paraffins (d) Aromatics, naphthenes, olefins, paraffins
Last Answer : Ans :d
Description : Smoke point of a test sample of kerosene is found to be 15 mm. On removal of __________ from it, the smoke point rises to 25 mm. (A) n-paraffins (B) Olefins (C) Aromatics (D) None of these
Last Answer : (C) Aromatics
Description : Which of the following has the highest octane number? (A) Aromatics (B) i-paraffins (C) Naphthenes (D) Olefins
Last Answer : (A) Aromatics
Description : Pyrolysis of kerosene or natural gasoline is done to produce mainly the (A) Olefins and aromatics (B) Lighter paraffins (C) Stabilised gasoline (D) Diesel
Last Answer : (A) Olefins and aromatic
Description : H/C ratio (by weight) for the same number of carbon atoms is the highest in case of (A) Aromatics (B) Paraffins (C) Olefins (D) Naphthenes
Last Answer : (D) Naphthenes
Description : Which of the following is the easiest to crack? (A) Paraffins (B) Olefins (C) Naphthenes (D) Aromatics
Last Answer : (A) Paraffins
Description : Reforming converts (A) Olefins into paraffins (B) Naphthenes into aromatics (C) Naphthenes into olefins (D) Naphthenes into paraffin
Last Answer : (B) Naphthenes into aromatics
Description : Which of the following has the lowest cetane number? (A) Aromatics (B) i-paraffins (C) Naphthene (D) Olefins
Description : Calorific value of (A) Light paraffinic fuel oils is equal to that of equivalent olefins (B) n-paraffin is lower than that of iso-paraffins of the same compounds (C) Light paraffinic fuel ... than that of equivalent olefins (D) Light paraffinic fuel oils is lower than that of equivalent olefins
Last Answer : (C) Light paraffinic fuel oils is higher than that of equivalent olefins
Description : Pick out the wrong statement. (A) Aromatics have higher specific gravity than paraffins (B) Gross calorific value (GCV) of petrofuels is equal to (12400 - 2100 ρ 2 ) where, ρ is the specific gravity ... volume basis (i.e., Kcal/litre) (D) Higher specific gravity of petrofuels means higher C/H ratio
Last Answer : (C) Heavier petrofuels have higher GCV on weight basis (i.e., Kcal/kg) but lower GCV on volume basis (i.e., Kcal/litre)
Description : Motoring test is conducted on IC engines to determine A. brake power B. indicated power C. friction power D. fuel consumption at full load
Last Answer : ANSWER : C
Description : Which of the following statement is not correct with respect to alcohols as alternate fuel in IC engines a) anti-knock characteristics of alcohol is poor b) alcohol contains about half the heat ... /litre c) alcohol does not vaporize as easily as gasoline d) alcohols are corrosive in nature
Last Answer : Answer: a Explanation: Anti-knock characteristics of alcohol is good.
Description : For same power output and same r, as compared to 2- stroke engines, four stroke SI engines have (a) Higher fuel consumption (b) Lower thermal efficiency (c) Highest exhaust temperatures (d) Higher thermal efficiency
Description : All heat engines utilize a. lower heating value of oil b. higher heating value of oil c. net calorific value of oil d. calorific value of fuel
Last Answer : ANSWER a. lower heating value of oil
Description : The air fuel ratio in petrol engines is controlled by a. valve opening / closing b. governing c. carburetion d. scavenging
Last Answer : ANSWER c. carburetion
Description : Olefins are generally represented by a) CnHn b) CnH2n c) CnH2n+2 d) CnH2n-6
Last Answer : Answer: a Explanation: Olefins are represented by CnHn and paraffins are generally represented by CnH2n+2.
Description : Paraffins have molecular structure of a) chain saturated b) chain unsaturated c) ring saturated d) ring unsaturated
Last Answer : Answer: a Explanation: None.
Description : Paraffins are generally represented by a) CnHn b) CnH2n c) CnH2n+2 d) CnH2n-6
Last Answer : Answer: c Explanation: Paraffins are generally represented by CnH2n+2 while olefins are generally represented by CnHn .
Description : What is the difference between paraffins and olefins?
Last Answer : Need answer
Description : Alkylation (A) Causes olefins to combine with each other (B) Causes olefins to combine with iso-paraffins (C) Converts iso-paraffin into olefin (D) Converts olefin into paraffin
Last Answer : (B) Causes olefins to combine with iso-paraffins
Description : Petroleum (A) Is optically active (B) Constitutes mainly of olefins (C) Does not contain asphalt (D) Does not contain aromatics
Last Answer : (A) Is optically active
Description : Isomerisation converts the __________ tot-paraffins. (A) Paraffins (B) Olefins (C) Naphthenes (D) None of these
Description : Polymerisation (A) Produces i-octane from cracked gases containing i-butane and butene (B) Causes olefins to combine with each other (C) Causes aromatics to combine with each other (D) Is aimed at producing lubricating oil
Last Answer : (B) Causes olefins to combine with each other
Description : The main reaction in reforming is the (A) Dehydrogenation of naphthenes (B) Hydrogenation of naphthenes (C) Hydrocracking of paraffins (D) Saturation of olefins
Last Answer : (A) Dehydrogenation of naphthenes
Description : Feedstock for polymerisation is (A) Naphtha (B) Cracked gases rich in C2 & C4 olefins (C) Low boiling aromatics (D) None of these
Last Answer : (B) Cracked gases rich in C2 & C4 olefins
Description : Coal tar (produced by high temperature carbonisation) is the main source of (A) Aromatic compounds (B) Aliphatic compounds (C) Paraffins (D) Olefins
Last Answer : (A) Aromatic compounds
Description : Pick out the wrong statement. (A) Lower boiling paraffins have higher octane number than higher paraffins (B) Dehydrogenation of naphthenes to aromatics is a desirable reaction in reforming ... is dearomatised kerosene (D) Catalyst used in catalytic reforming is platinum on silica-alumina base
Last Answer : (C) The most ideal feedstock for thermal reforming is dearomatised kerosene
Description : Which is the most desirable component of a good quality kerosene? (A) i-paraffins (B) Aromatics (C) n-paraffins (D) Naphthenes
Last Answer : (C) n-paraffins
Description : Pick out the correct statement. (A) Paraffins have higher octane number than corresponding iso-paraffin (B) Paraffins have lower smoke point than aromatics
Last Answer : (B) Paraffins have lower smoke point than aromatics
Description : Choose the correct statement. (A) Octane number of i-octane is zero (B) Octane number of paraffins increases with increasing number of carbon atoms (C) Branched chain paraffins have higher octane ... atoms (D) The aromatics have lower octane number than naphthenes with same number of carbon atoms
Last Answer : (A) Octane number of i-octane is zero
Description : Which of the following has the highest gum forming tendency in gosoline? (A) Paraffins (B) Diolefins (C) Aromatics (D) Naphthenes
Last Answer : (B) Diolefins
Description : Which is the most undesirable component in kerosene? (A) Aromatics (B) i-paraffins (C) n-paraffins (D) Naphthenes
Description : Which of the following hydrocarbons of same carbon atoms has minimum smoking tendency? (A) Paraffins (B) Naphthenes (C) Aromatics (D) Iso-paraffins
Description : Pick out the wrong statement about the smoking tendency of various hydrocarbon constituents of kerosene. (A) Smoking tendency of hydrocarbons increases in the order: paraffins → isoparaffins → naphthenes → aromatics (B) Smoking tendency of paraffins increases with decrease in its molecular weight
Last Answer : (B) Smoking tendency of paraffins increases with decrease in its molecular weight
Description : Which of the following is desirable in diesel and kerosene but is undesirable in gasoline? (A) Aromatics (B) Mercaptans (C) Paraffins (D) Naphthenic acid
Description : Which of the following is desirable in petrol (gasoline) but undesirable in kerosene? (A) Paraffins (B) Aromatics (C) Mercaptans
Last Answer : (C) Mercaptans
Description : Pick out the wrong statement. (A) Higher specific gravity of petroleum products means higher C/H ratio (B) Aromatics have lower specific gravity than corresponding paraffins (C) Hydrocarbons of low ... of high specific gravity (e.g., aromatics) possess the maximum thermal energy per unit weight
Last Answer : (B) Aromatics have lower specific gravity than corresponding paraffins
Description : Extractor temperature is maintained at -20°C in Edeleanu process to reduce the __________ of kerosene. (A) Smoke point (B) Paraffins (C) Aromatics (D) Naphthenes
Last Answer : (B) Paraffins
Description : Good quality kerosene should have (A) Low smoke point (B) High smoke point (C) High aromatics content (D) Low paraffins content
Last Answer : (B) High smoke point
Description : Supercharging is essential in A. aircraft engines B. petrol engines C. gas turbines D. diesel engines
Last Answer : ANSWER : A
Description : Morse test is conducted on the engine to calculate the mechanical efficiency of A. single cylinder CI engine B. single cylinder SI engine C. only on two stroke engines D. multi cylinder engine
Last Answer : ANSWER : D
Description : In spark ignition engines, the knocking tendency can be decreased by a) decreasing compression ratio b) controlling intake throttle c) controlling ignition timing d) adding dopes like tetraethyl lead and ethylene dibromide
Last Answer : Answer: d Explanation: None.
Description : Alcohols alone cannot be used in CI engines as a) their self ignition temperature is high b) latent heat of vaporization is high c) all of the mentioned d) none of the mentioned
Last Answer : Answer: c Explanation: None.
Description : With EFI of diesel engines a) sharp start and stop is not possible b) very high injection pressure can be obtained c) sudden cylinder cut-off is impossible d) diagnostic properties are poor
Last Answer : Answer: b Explanation: Generally, with EFI of diesel engines very high injection pressure can be obtained.
Description : Anti-knock for compression ignition engines is a) napthene b) tetra ethyl lead c) amyl nitrate d) hexadecane
Last Answer : Answer: c Explanation: Amyl nitrate is the anti-knock for compression ignition engines.
Description : The knocking tendency in CI engines increases with (a) Increase of coolant water temperature (b) Increase of temperature of inlet air (c) Decrease of compression ratio (d) Increase of compression ratio
Last Answer : Ans :c
Description : Which of the following factors increases the tendency of knocking in the CI engines? (a) Increasing both the r and coolant temperatures (b) Increasing both the speed and the injection advance (c) Increasing the speed, injection advance and coolant temperature (d) Increasing the compression ratio
Description : In SI engines knocking can be reduced by (a) Increasing the compression ratio (b) Increasing the cooling water temperature (c) Retarding the spark advance (d) Increasing the inlet air temperature
Description : Which one of the following types of compressor is mostly used for supercharging of IC engines? (a) Radial flow compressor (b) Axial flow compressor (c) Root blower (d) Reciprocating compressor
Last Answer : Ans : c