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 : For S.I. engines fuel most preferred are a) aromatics b) paraffins c) olefins d) napthenes
Last Answer : Answer: a Explanation: For S.I. engines fuel most preferred are aromatics while for C.I. engines fuel most preferred are paraffins.
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 : 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 : Which of the following has the highest octane number? (A) Aromatics (B) i-paraffins (C) Naphthenes (D) Olefins
Last Answer : (A) Aromatics
Description : Isomerisation converts the __________ tot-paraffins. (A) Paraffins (B) Olefins (C) Naphthenes (D) None of these
Last Answer : (A) Paraffins
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 : 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
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 : 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 : 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 : What is Alkyne or Olefins ?
Last Answer : Hydrocarbons that have two carbon atoms joined together by a double bond in a carbon chain are called alkynes or olefins.
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 : In catalytic cracking process, olefins crack __________ times faster than in thermal cracking process. (A) 100 (B) 200-300 (C) 1000-10000 (D) 10
Last Answer : (C) 1000-10000
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 : 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 : Which is almost absent in crude petroleum? (A) Olefins (B) Mercaptans (C) Naphthenes (D) Cycloparaffins
Last Answer : (B) Mercaptans
Description : Olefins are (A) Saturated hydrocarbons (B) Unsaturated cyclic compounds (hydrocarbons) (C) Present in substantially good quantity in crude petroleum (D) None of these
Last Answer : (D) None of these
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 : Liquefied Petroleum Gas (LPG) is mainly a mixture of (A) Propane & butane (B) Methane & ethane (C) High boiling olefins (D) High boiling naphthenes
Last Answer : (A) Propane & butane
Description : The general formula of naphthenes is (A) CnH2n + 2 (B) CnH2n-6 (where, n ≥ 6) (C) CnHn-4 (D) Same as that for olefins i.e. CnH2n
Last Answer : (B) CnH2n-6 (where, n ≥ 6)
Description : CnH2n is the general formula for (A) Olefins (B) Naphthenes (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : How will you demonstrate that double bonds of benzene are somewhat different from that of olefins?
Last Answer : Ans. The double bonds of olefins decolorize bromine water and discharge the pink colour of Bayer‘s reagent while those of benzene not.
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 : 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 : __________ converts n-paraffins to i-paraffins. (A) Alkylation (B) Polymerisation (C) Isomerisation (D) None of these
Last Answer : (C) Isomerisation
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. (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 : 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 : Paraffins are desirable in lubricating oil, as it has got high (A) Viscosity (B) Viscosity index (C) Smoke point (D) Pour poin
Last Answer : (C) Smoke point
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 : Which of the following reactions is undesirable in the production of catalytically reformed gasoline? (A) Dehydrogenation of Naphthene (B) Dehydrogenation of lower paraffins (C) Dehydrocyclization of higher paraffins (D) Isomerisation of paraffins
Last Answer : (B) Dehydrogenation of lower paraffins
Description : What are alkanes? Why are they called paraffins?
Last Answer : Ans. Those hydrocarbons which contain single bond between carbon- carbon are called alkanes. They are called paraffins because they are very less reactive (Latin- Parum= little, affins = affinity)
Description : Why are alkanes called paraffins?
Last Answer : Paraffin’s means little affinity; alkanes due to strong C-C and C-H bonds are relatively chemically inert.
Description : Why are alkanes referred to as paraffins?
Last Answer : Paraffin is derived from the Latin word meaning ‘less activity’. Alkanes are compounds which undergo few reactions. Hence they are referred to as paraffins.