A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted

A fuel containing carbon and carbon monoxide (but containing no
hydrogen or its compounds) is burnt in pure oxygen at constant pressure.
Its gross calorific value as compared to net calorific value will be
(A) More
(B) Less
(C) Same
(D) Data insufficient; can't be predicted
by

1 Answer

Answer :

(C) Same
by

Related questions

A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large quantity of hydrogen in the fuel (B) Low calorific value of the fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air

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Last Answer : (D) Lack of thorough mixing of fuel with air

Gross and net calorific value of a fuel will be the same (A) If its ash content is zero (B) If its carbon content is very low (C) If its hydrogen/hydrogen compound content is zero (D) Under no circumstances

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Last Answer : (C) If its hydrogen/hydrogen compound content is zero

A chemical reaction, A → 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is (A) 0.33 (B) 0.5 (C) 1 (D) Data insufficient, can't be predicted

Description : A chemical reaction, A → 3B, is conducted in a constant pressure vessel. Starting with pure A, the volume of the reaction mixture increases 3 times in 6 minutes. The fractional conversion is (A) 0.33 (B) 0.5 (C) 1 (D) Data insufficient, can't be predicted

Last Answer : (C) 1

Pick out the wrong statement: (A) Carburetted water gas is also called blue gas (B) Coals are divided in four species according to their carbon content in Seylor's classification (C) Carbonisation time in a by-product coke oven is about 16 hours (D) Gross and net calorific value of a fuel is the same, if it does not contain hydrogen or hydrocarbons

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The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is (A) Less pronounced (B) More pronounced (C) Equal (D) Data insufficient, can't be predicted

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Last Answer : (B) More pronounced

In low temperature carbonisation of coal as compared to high temperature carbonisation __________ produced is less. (A) Difference in gross & net calorific value of the coke oven gas (B) Free carbon content in tar (C) Yield percentage of coke (D) Yield of ammonia present in coke oven gas

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Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value

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The activity of an ideal gas is numerically __________ its pressure. (A) More than (B) Less than (C) Equal to (D) Data insufficient, can't be predicted

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Last Answer : (C) Equal to

In a first order reaction, the time required to reduce the concentration of reactant from 1 mole/litre to 0.5 mole/litre will be __________ that requiredto reduce it from 10 moles/litre to 5 moles/litre in the same volume.(A) More than(B) Less than(C) Same as(D) Data insufficient; can't be predicted

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Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the (A) Calorific value (B) Heat of reaction (C) Heat of combustion (D) Heat of formation

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. For the same feed, feed quality and separation (in a distillation column), with the increase of total pressure, the number of ideal plates will (A) Increase (B) Decrease (C) Remain same (D) Data insufficient, can't be predicted

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Last Answer : (A) Increase

As the time is passing, entropy of the universe (A) Is increasing (B) Is decreasing (C) Remain constant (D) Data insufficient, can't be predicted

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A coal gasifier operating at 20 atm. (e.g. Lurgi gasifier) as compared to one operating at atmospheric pressure (e.g. Kopper-Totzek or Winkler gasifier) will produce a gas having (A) Higher methane content and thus higher calorific value (B) Higher carbon monoxide content(C) Lower carbon dioxide content(D) None of these

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Last Answer : (A) Higher methane content and thus higher calorific value

Bomb calorimeter is used to determine the (where, GCV - Gross Calorific Value. NCV - Net Calorific Value.) (A) GCV at constant pressure (B) GCV at constant volume (C) NCV at constant pressure (D) NCV at constant volume

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Last Answer : (C) NCV at constant pressure

Calorific value as determined by bomb calorimeter is the (A) Higher calorific value at constant volume(B) Gross calorific value at constant pressure(C) Lower calorific value at constant pressure(D) Net calorific value at constant volume

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Last Answer : (A) Higher calorific value at constant volume

One kilogram of water at 0°C is changed to superheated steam of one atm pressure and 300° C. The major heat consumption in the process will be to (A) Heat the water from 0°C to 100°C (B) Evaporate the water (C) To superheat the steam (D) Data insufficient, can't be predicted

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Presence of __________ in a dry gaseous fuel does not contribute to its calorific value. (A) Sulphur (B) Oxygen (C) Hydrogen (D) Carbon

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A first order reaction requires two unequal sized CSTR. Which of thefollowing gives higher yield?(A) Large reactor followed by smaller one(B) Smaller reactor followed by larger one(C) Either of the arrangement (A) or (B) will give the same yield(D) Data insufficient, can't be predicted

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With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will (A) Increase (B) Decrease (C) Remain same (D) Data in insufficient; can't be predicted

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Last Answer : (A) Increase

With the same reaction time, initial concentration and feed rate, the reaction 2A → B is carried out separately in CSTR and P.F. reactor of equal volumes. The conversion will be (A) Higher in P.F. reactor (B) Higher in CSTR (C) Same in both the reactors (D) Data insufficient; can't be predicted

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Last Answer : (A) Higher in P.F. reactor

Out of the following fuels, the difference between the net and gross calorific value is maximum in case of (A) Pitch (B) Fuel oil (C) Blast furnace gas (D) Bituminous coal

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Power loss in an orificemeter is __________ that in a Venturimeter. (A) Less than (B) Same as (C) More than (D) Data insufficient, cannot be predicted

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At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid __________ that in dry packed tower. (A) Is greater than (B) Is lower than (C) Is same as (D) Cannot be predicted as data are insufficient

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Last Answer : (A) Is greater than

Sensible heat absorbed by 1 lb of water when it is heated from 32 to 212°F may be around __________ BTU. (A) 180 (B) 970 (C) 3.97 (D) Data insufficient, can't be predicted

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Rate determining step in a reaction consisting of a number of steps inseries is the __________ step.(A) Fastest(B) Slowest(C) Intermediate(D) Data insufficient; can't be predicted

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Last Answer : (B) Slowest

For an isothermal process, the internal energy of a gas (A) Increases (B) Decreases (C) Remains unchanged (D) Data insufficient, can't be predicted

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Last Answer : (C) Remains unchanged

Net calorific value is the gross calorific value less the __________ heat of water in the product of combustion when cooled to 15°C(A) Sensible (B) Latent (C) Sensible and latent (D) None of these.

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A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has been used for combustion (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Description : A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has ... (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Last Answer : (C) Complete combustion of fuel has taken place

Pitch (a product of coal tar distillation) is always mixed with creosote oil, when it is to be burnt in a burner, because (A) Its calorific value is very less (B) Tar neutralises the residual acids present in pitch (C) It reduces viscosity and imparts fluidity for its transportation through pipelines at economic pressure drop (D) All (A), (B) and (C)

Description : Pitch (a product of coal tar distillation) is always mixed with creosote oil, when it is to be burnt in a burner, because (A) Its calorific value is very less (B) Tar neutralises the residual acids ... for its transportation through pipelines at economic pressure drop (D) All (A), (B) and (C)

Last Answer : (C) It reduces viscosity and imparts fluidity for its transportation through pipelines at economic pressure drop

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Description : (1) the action of ultraviolet rays on oxygen Explanation: The majority of tropospheric ozone formation occurs when nitrogen oxides (NOx), carbon monoxide (CO ) and volatile organic compounds (VOCs), such as xylene, ... violet rays. NOx, CO, and VOCs are called ozone precursors. CO + 2O2 + CO2 + O3

Last Answer : Water is not effective in extinguishing a fire caused by petrol because - (1) the flame is too hot for water to cool it down (2) water and petrol react chemically (3) water and petrol are ... (4) water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn

Gross & net calorific value is the same for (A) Blast furnace gas (B) Coke oven gas (C) L.D. converter gas (D) None of these

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A gaseous fuel in order to develop luminosity on burning, must contain (A) Carbon monoxide (B) Hydrocarbons (C) Hydrogen (D) Oxygen

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Last Answer : (B) Hydrocarbons

Which of the following constituents of a fuel does not contribute to its calorific value on combustion? (A) Hydrogen (B) Sulphur (C) Carbon (D) None of these

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Last Answer : (D) Calorific value of natural gas is more than that of LPG

Pick out the wrong statement. (A) Pulverised fuel can be completely burnt with less percentage of excess air compared to lump coal (B) Low grade coal can be used, but generally high volatile matter coals are more suitable for making pulverised fuel (C) Regulation of furnace temperature and atmosphere (oxidising or reducing) is easily possible with pulverised fuel firing (D) None of these

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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)

In high temperature carbonisation (as compared to low temperature carbonisation) of coal (A) Coke oven gas yield is more (B) Tar yield is less but free carbon in tar is more (C) Calorific value of coke oven gas is less (D) All (A), (B) and (C)

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Last Answer : (D) All (A), (B) and (C)

Pure carbon is completely burnt in oxygen. The flue gas analysis is 70%CO2 , 20%CO and 10%O2 . The percent excess oxygen used is (A) 20 (B) 12.5 (C) 0 (D) 10

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Last Answer : (C) 0

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Last Answer : (D) All (A), (B) and (A)

6 gm of carbon is burnt with an amount of air containing 18 gm oxygen. The product contains 16.5 gms CO2 and 2.8 gms CO besides other constituents. What is the degree of conversion on the basis of disappearance of limiting reactant? (A) 100% (B) 95% (C) 75% (D) 20%

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Out of the following fuels, the difference between gross and net calorific value will be minimum in case of (A) Coke oven gas (B) Water gas (C) Natural gas (D) Blast furnace gas

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Last Answer : (D) Blast furnace gas

Gross calorific value will be equal to the net calorific value for (A) H2 (B) C2H2 (C) CO (D) C2H6

Description : Gross calorific value will be equal to the net calorific value for (A) H2 (B) C2H2 (C) CO (D) C2H6

Last Answer : (C) CO

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 oils is higher than that of equivalent olefins (D) Light paraffinic fuel oils is lower than that of equivalent olefins

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Last Answer : (C) Light paraffinic fuel oils is higher than that of equivalent olefins

Proteins are most complex organic compounds, containing a. Carbon b. Hydrogen c. oxygen and nitrogen d. All of these

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Last Answer : All of these

The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be (A) More (B) Less (C) Same (D) Data insufficient to predict

Description : The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be (A) More (B) Less (C) Same (D) Data insufficient to predict

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Initial pressure of oxygen introduced into the 'bomb' of the bomb calorimeter for determination of calorific value of coal/fuel oil may be around __________ atm. (A) 3-5 (B) 25-30 (C) 60-65 (D) 95-100

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The maximum adiabatic flame temperature in air as compared to that in pure oxygen is (A) Much lower (B) Much higher (C) Same (D) Either lower or higher, depends on the type of fuel

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Explain the following a) Dry Bulb Temperature and Wet bulb Temperature b) Maximum Demand and Power Factor c) Gross Calorific Value & Net Calorific Value d) 5S & Return of Investment (ROI) e) CUSUM

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Define calorific value. Differentiate between net calorific value and gross calorific value.

Description : Define calorific value. Differentiate between net calorific value and gross calorific value.

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Explain higher and lower calorific value of a coal having following composition by mass Carbon 81%,Hydrogen 7%, Oxygen 8%,Nitrogen 2.5%, sulphur 1.5% and remaining is ash

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