- (A) Moderate changes in operating temperature does not change the depth of cracking
- (B) Increased residence time results in the decreased severity of cracking
- (C) At low pressure, the yield of lighter hydrocarbons are more
- (D) Greater depth of cracking gives lower octane number gasoline
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- (A) Iso-paraffin crack faster than n-paraffin.
- (B) Catalytic cracking is endothermic, but the regeneration of catalyst is exothermic
- (C) Rate of decomposition of olefins in catalytic cracking is slightly slower than the thermal cracking
- (D) None of these
- (A) Pensky-Marten apparatus is used for determining flash points above 50°C
- (B) Characterisation factor of paraffinic crude oil is more than 12
- (C) Abel apparatus is used for determining flash points below 50°C
- (D) An oil having high susceptibility to change in viscosity with temperature changes, has a high viscosity index
- (A) Aromatics have higher specific gravity than paraffins
- (B) Gross calorific value (GCV) of petrofuels is equal to (12400 – 2100 ρ2) where, ρ is the specific gravity of the fuel at 15.5°C
- (C) Heavier petrofuels have higher GCV on weight basis (i.e., Kcal/kg) but lower GCV on volume basis (i.e., Kcal/litre)
- (D) Higher specific gravity of petrofuels means higher C/H ratio
- (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 number than straight chain paraffins with same number of carbon atoms
- (D) The aromatics have lower octane number than naphthenes with same number of carbon atoms
- (A) Coking tendency increases with increasing molecular weight
- (B) Coking tendency decreases with increasing molecular weight
- (C) Higher pressure enhances coke formation
- (D) Coking is an exothermic reaction
- (A) Paraffins have higher octane number than corresponding iso-paraffin
- (B) Paraffins have lower smoke point than aromatics
- (C) Suitability of kerosene as a fuel & as an illuminant may be determined by char value test
- (D) Aviation fuel should have very high cloud point
- (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition
- (B) Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction
- (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot
- (D) Presence of inerts affects the equilibrium conversion of
- (A) A particular chemical reaction is more temperature sensitive at low temperatures
- (B) A very high value of equilibrium constant, K (K >> 1) indicates that the reaction is practically irreversible in nature
- (C) The intercept of the Arrhenius plot is called the ‘activation energy’
- (D) Non-ideal flow takes place in reactors due to recycling, channeling or by creation of stagnant regions
- (A) A lower temperature favours the reaction of lower activation energy
- (B) The dispersion number for a reactor/vessel is uL/D
- (C) The rate controlling step in a reaction involving many steps is the fastest step
- (D) Pore volume and porosity of a catalyst is measured by Brunauer-Emmett-Teller (BET) technique
