The maximum adiabatic flame temperature in air is __________ the maximum flame temperature in pure oxygen. (A) Lower than (B) Higher than(C) Same as(D) Not related to

The maximum adiabatic flame temperature in air is __________ the
maximum flame temperature in pure oxygen.
(A) Lower than
(B) Higher than
(C) Same as
(D) Not related to
by

1 Answer

Answer :

(A) Lower than
by

Related questions

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

Description : 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

Last Answer : (A) Much lower

The ratio of maximum adiabatic flame temperature in air to that in pure oxygen is always (A) 1 (B) < 1 (C) > 1 (D) Unpredictable

Description : The ratio of maximum adiabatic flame temperature in air to that in pure oxygen is always (A) 1 (B) < 1 (C) > 1 (D) Unpredictable

Last Answer : (B) < 1

Pick out the wrong statement. (A) Theoretical flame temperature is the temperature attained by the products of combustion, when the fuel is burned without loss or gain of heat (B) Burning the fuel with theoretically required amount of pure oxygen results in attainment of maximum adiabatic flame temperature (C) Burning the fuel with excess pure oxygen results in maximum theoretical flame temperature (D) Adiabatic flame temperatures of actual combustions are always less than the maximum values

Description : Pick out the wrong statement. (A) Theoretical flame temperature is the temperature attained by the products of combustion, when the fuel is burned without loss or gain of heat (B) ... flame temperature (D) Adiabatic flame temperatures of actual combustions are always less than the maximum values

Last Answer : (C) Burning the fuel with excess pure oxygen results in maximum theoretical flame temperature

The maximum adiabatic flame temperature is attained, when the fuel is burnt with (A) Theoretically required amount of air(B) More than theoretically required amount of air(C) Less than theoretically required amount of air(D) Theoretically required amount of oxygen

Description : The maximum adiabatic flame temperature is attained, when the fuel is burnt with (A) Theoretically required amount of air (B) More than theoretically required amount of air (C) Less than theoretically required amount of air (D) Theoretically required amount of oxygen

Last Answer : (D) Theoretically required amount of oxygen

Coke oven gas is a better fuel than blast furnace gas, because of its higher (A) Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity) (B) Adiabatic flame temperature (C) Heat release rate (thus requiring smaller combustion chamber) (D) All (A), (B) and (C)

Description : Coke oven gas is a better fuel than blast furnace gas, because of its higher (A) Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity) (B) Adiabatic flame temperature ... release rate (thus requiring smaller combustion chamber) (D) All (A), (B) and (C)

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

Actual flame temperature is always lower than the adiabatic flame temperature, because there is (A) No possibility of obtaining complete combustion at high temperature (B) Always loss of heat from the flame (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : Actual flame temperature is always lower than the adiabatic flame temperature, because there is (A) No possibility of obtaining complete combustion at high temperature (B) Always loss of heat from the flame (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

Preheating of combustion air is done to (A) Increase the adiabatic flame temperature (B) Increase the calorific value of the fuel (C) Complete the combustion of fuel (D) Reduce its requirement for effecting the complete combustion

Description : Preheating of combustion air is done to (A) Increase the adiabatic flame temperature (B) Increase the calorific value of the fuel (C) Complete the combustion of fuel (D) Reduce its requirement for effecting the complete combustion

Last Answer : (A) Increase the adiabatic flame temperature

For the case of a fuel gas undergoing combustion with air, if the air/fuel ratio is increased, the adiabatic flame temperature will (A) Increase (B) Decrease (C) Increase or decrease depending on the fuel type (D) Not change

Description : For the case of a fuel gas undergoing combustion with air, if the air/fuel ratio is increased, the adiabatic flame temperature will (A) Increase (B) Decrease (C) Increase or decrease depending on the fuel type (D) Not change

Last Answer : (B) Decrease

Adiabatic flame temperature of a fuel is dependent on the initial temperature of (A) Fuel (B) Air (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Adiabatic flame temperature of a fuel is dependent on the initial temperature of (A) Fuel (B) Air (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Combustion of pulverised coal compared to the lumpy coal (A) Provides better control of furnace temperature (B) Facilitates combustion with lower excess air (C) Provides higher thermal efficiency & flame temperature (D) All (A), (B) & (C)

Description : Combustion of pulverised coal compared to the lumpy coal (A) Provides better control of furnace temperature (B) Facilitates combustion with lower excess air (C) Provides higher thermal efficiency & flame temperature (D) All (A), (B) & (C)

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

Combustion of fuel in a furnace with oxygen enriched air results in higher (A) Flue gas volume (B) Flame temperature (C) Fuel consumption (D) Stack loss

Description : Combustion of fuel in a furnace with oxygen enriched air results in higher (A) Flue gas volume (B) Flame temperature (C) Fuel consumption (D) Stack loss

Last Answer : (B) Flame temperature

A coal containing high amount of volatile matter will have (A) Low ignition temperature (B) Very little ash content (C) High fusion point of its ash (D) Low adiabatic flame temperature

Description : A coal containing high amount of volatile matter will have (A) Low ignition temperature (B) Very little ash content (C) High fusion point of its ash (D) Low adiabatic flame temperature

Last Answer : (A) Low ignition temperature

A fuel with high heat release rate will (A) Require smaller combustion chamber (B) Have high calorific value (C) Have high adiabatic flame temperature (D) None of these

Description : A fuel with high heat release rate will (A) Require smaller combustion chamber (B) Have high calorific value (C) Have high adiabatic flame temperature (D) None of these

Last Answer : (A) Require smaller combustion chamber

Blast furnace gas compared to coke oven gas has (A) Lower ignition temperature (B) Narrower limit of inflammability (C) Higher calorific value (D) Lower theoretical flame temperature

Description : Blast furnace gas compared to coke oven gas has (A) Lower ignition temperature (B) Narrower limit of inflammability (C) Higher calorific value (D) Lower theoretical flame temperature

Last Answer : (D) Lower theoretical flame temperature

Ignition temperature of a fuel in air is __________ that in pure oxygen. (A) More than(B) Less than(C) Equal to(D) Either more or less; depends on the type of fuel

Description : Ignition temperature of a fuel in air is __________ that in pure oxygen. (A) More than (B) Less than (C) Equal to (D) Either more or less; depends on the type of fuel

Last Answer : (A) More than

The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at __________ percent relative humidity. (A) 0 (B) 100 (C) 50 (D) None of these

Description : The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at __________ percent relative humidity. (A) 0 (B) 100 (C) 50 (D) None of these

Last Answer : Option B

Relative to the pure solvent, the boiling point of a solution is: w) higher x) lower y) at the same temperature

Description : Relative to the pure solvent, the boiling point of a solution is: w) higher x) lower y) at the same temperature

Last Answer : ANSWER: W -- HIGHER

The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit conversion is 20%, then the exit temperature (in k) is (Data: Heat of reaction at 298 K = - 50000 kJ/ kmole of A reacted Heat capacities CPA = CPB = 100kJ/kmole. K (may be assumed to be independent of temperature)) (A) 400 (B) 500 (C) 600 (D) 1000

Description : The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit ... /kmole. K (may be assumed to be independent of temperature)) (A) 400 (B) 500 (C) 600 (D) 1000

Last Answer : (C) 600

With increase in calorific value of fuels, their adiabatic flame temperatures (A) Increase (B) Decrease (C) Remain unchanged (D) May increase or decrease; depends on the quantity of products of combustion

Description : With increase in calorific value of fuels, their adiabatic flame temperatures (A) Increase (B) Decrease (C) Remain unchanged (D) May increase or decrease; depends on the quantity of products of combustion

Last Answer : (D) May increase or decrease; depends on the quantity of products of combustion

Combustion of pulverised coal as compared to that of lump coal (A) Develops a non-luminous flame (B) Develops a low temperature flame (C) Can be done with less excess air (D) Provides a lower rate of heat release

Description : Combustion of pulverised coal as compared to that of lump coal (A) Develops a non-luminous flame (B) Develops a low temperature flame (C) Can be done with less excess air (D) Provides a lower rate of heat release

Last Answer : (C) Can be done with less excess ai

Oxygen enrichment of combustion air does not result in increase of the (A) Flame temperature (B) Oxygen in the flue gas (C) Stack loss (D) Heat transfer rate in the furnace

Description : Oxygen enrichment of combustion air does not result in increase of the (A) Flame temperature (B) Oxygen in the flue gas (C) Stack loss (D) Heat transfer rate in the furnace

Last Answer : (B) Oxygen in the flue gas

Theoretical flame temperature of a fuel is that temperature which is attained, when the fuel is completely burnt 'using theoretical amount of air in (A) Air (B) Oxygen (C) Either (A) or (B) (D) Either (A) or (B) without gain or loss of heat

Description : Theoretical flame temperature of a fuel is that temperature which is attained, when the fuel is completely burnt 'using theoretical amount of air in (A) Air (B) Oxygen (C) Either (A) or (B) (D) Either (A) or (B) without gain or loss of heat

Last Answer : (D) Either (A) or (B) without gain or loss of heat

__________ temperature remains constant during adiabatic saturation process of unsaturated air. (A) Dew point (B) Dry bulb (C) Wet bulb (D) None of these

Description : __________ temperature remains constant during adiabatic saturation process of unsaturated air. (A) Dew point (B) Dry bulb (C) Wet bulb (D) None of these

Last Answer : (C) Wet bulb

__________ remains constant during the adiabatic cooling of moist air. (A) Wet bulb temperature (B) Dry bulb temperature (C) Relative humidity (D) Specific humidity

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Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy state, they emit light, which we can observe in - (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence

Last Answer : (3) Emission spectra Explanation: When a metal atom is strongly heated, its electrons absorb the heat energy and jump to a higher energy level. When the electron returns to its original position it ... to the energy the electron has released at each stage °fits fall back to its original state.

When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy siate, they emit light, which we can observe in (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence

Description : When a metal is heated in a flame, the electrons absorb energy and jump to higher energy state. On coming back to the lower energy siate, they emit light, which we can observe in (1) Raman spectra (2) Absorption spectra (3) Emission spectra (4) Fluorescence

Last Answer : Emission spectra

Preheating of __________ the flame temperature. (A) The gaseous fuel before combustion decreases (B) Combustion air decreases (C) Either the fuel or the air or both, increases (D) Either the fuel or the air does not affect

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Last Answer : (C) Either the fuel or the air or both, increases

Pick out the wrong statement. (A) Biological oxygen demand (B.O.D.) value of a sewerage sample is always lower than its chemical oxygen demand (C.O.D.) value (B) Environmental pollution by NOx emission is much higher by four stroke petrol engines as compared to the two stroke engines (C) Temperature in stratosphere rises with increasing altitude (D) The characteristic of a green house body is that it allows the long wavelength incoming solar radiation to come in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Description : Pick out the wrong statement. (A) Biological oxygen demand (B.O.D.) value of a sewerage sample is always lower than its chemical oxygen demand (C.O.D.) value (B) Environmental pollution by ... in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Last Answer : (D) The characteristic of a green house body is that it allows the long wavelength incoming solar radiation to come in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

In general, the limit of inflammability/explosion limit of fuel gases is widened by the (A) Increase in gas pressure (B) Increase in temperature (i.e. preheating) (C) Use of pure oxygen for combustion instead of air (D) All (A), (B) & (C)

Description : In general, the limit of inflammability/explosion limit of fuel gases is widened by the (A) Increase in gas pressure (B) Increase in temperature (i.e. preheating) (C) Use of pure oxygen for combustion instead of air (D) All (A), (B) & (C)

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

Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure to the air with a wet bulb temperature of 60°C, then both the approach & the range would be 10°C (C) For unsaturated air-water vapor mixture at atmospheric conditions, the wet bulb temperature & adiabatic cooling lines are the same (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure

Description : Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure ... & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure

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A metallic alloy in general as compared to their pure metal components is (A) More corrosion resistant (B) Having higher melting point (C) Having lower hardness, reactivity and fusibility (D) Having lower electrical conductivity

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Last Answer : Answer: D

Maximum work that could be secured by expanding the gas over a given pressure range is the __________ work. (A) Isothermal (B) Adiabatic (C) Isentropic (D) None of these

Description : Maximum work that could be secured by expanding the gas over a given pressure range is the __________ work. (A) Isothermal (B) Adiabatic (C) Isentropic (D) None of these

Last Answer : (A) Isothermal

The surface tension of mercury at normal temperature is __________ that of water. (A) Same as (B) Lower than (C) Higher than (D) None of these

Description : The surface tension of mercury at normal temperature is __________ that of water. (A) Same as (B) Lower than (C) Higher than (D) None of these

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Last Answer : (B) Is always greater than

A fresh egg sinks in pure water but floats in salty water. This is because (a) Saline water is denser than pure water (b) Saline water is lighter than pure water (c) The viscosity of saline water is higher than that of pure water (d) The surface tension of saline water is lower than that of pure water

Description : A fresh egg sinks in pure water but floats in salty water. This is because (a) Saline water is denser than pure water (b) Saline water is lighter than pure water (c) The viscosity of saline water ... than that of pure water (d) The surface tension of saline water is lower than that of pure water

Last Answer : Ans:(a)

When a solute is dissolved in a pure solvent, the resulting freezing point is: w) higher than pure solvent x) lower than pure solvent y) does not change z) cannot tell from this information

Description : When a solute is dissolved in a pure solvent, the resulting freezing point is: w) higher than pure solvent x) lower than pure solvent y) does not change z) cannot tell from this information

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Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature. (A) Higher (B) Much higher (C) Lower (D) Much lower

Description : Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature. (A) Higher (B) Much higher (C) Lower (D) Much lower

Last Answer : (D) Much lower

When the psychometric ratio is __________ then the adiabatic saturation temperature and wet bulb temperature becomes equal. (A) 1 (B) < 1 (C) > 1 (D) ∞

Description : When the psychometric ratio is __________ then the adiabatic saturation temperature and wet bulb temperature becomes equal. (A) 1 (B) < 1 (C) > 1 (D) ∞

Last Answer : (A) 1

Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Description : Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Last Answer : (B) Wet-bulb

In a/an __________ reactor, there is exchange of heat with the surroundings with sizeable temperature variation. (A) Adiabatic (B) Isothermal (C) Non-adiabatic (D) None of these

Description : In a/an __________ reactor, there is exchange of heat with the surroundings with sizeable temperature variation. (A) Adiabatic (B) Isothermal (C) Non-adiabatic (D) None of these

Last Answer : (C) Non-adiabatic

__________ decreases during adiabatic throttling of a perfect gas. (A) Entropy (B) Temperature (C) Enthalpy (D) Pressure

Description : __________ decreases during adiabatic throttling of a perfect gas. (A) Entropy (B) Temperature (C) Enthalpy (D) Pressure

Last Answer : (D) Pressure

The work done in an adiabatic change in a particular gas depends upon changes in the __________ only. (A) Temperature (B) Specific heat (C) Volume (D) Pressure

Description : The work done in an adiabatic change in a particular gas depends upon changes in the __________ only. (A) Temperature (B) Specific heat (C) Volume (D) Pressure

Last Answer : (A) Temperature

In case of an __________ process, the temperature of the system increases. (A) Isothermal compression (B) Isothermal expansion (C) Adiabatic expansion (D) Adiabatic compression

Description : In case of an __________ process, the temperature of the system increases. (A) Isothermal compression (B) Isothermal expansion (C) Adiabatic expansion (D) Adiabatic compression

Last Answer : (D) Adiabatic compression

High value of BOD (Biochemical Oxygen Demand) indicates that (a) water is less polluted (b) consumption of organic matter in the water is higher by the microbes (c) water is pure (d) water is highly polluted.

Description : High value of BOD (Biochemical Oxygen Demand)  indicates that (a) water is less polluted (b) consumption of organic matter in the water is  higher by the microbes  (c) water is pure (d) water is highly polluted.

Last Answer : (b) consumption of organic matter in the water is 

High value of BOD (Biochemical Oxygen Demand) indicates that (a) water is less polluted (b) consumption of organic matter in the water is higher by the microbes (c) water is pure (d) water is highly polluted.

Description : High value of BOD (Biochemical Oxygen Demand) indicates that (a) water is less polluted (b) consumption of organic matter in the water is higher by the microbes (c) water is pure (d) water is highly polluted.

Last Answer : (b) consumption of organic matter in the water is higher by the microbes

The haemoglobin of a human fetus (a) has only 2 protein subunits instead of 4 (b) has a higher affinity for oxygen than that of an adult (c) has a lower affinity for oxygen than that of the adult (d) its affinity for oxygen is the same as that of an adult.

Description : The haemoglobin of a human fetus (a) has only 2 protein subunits instead of 4 (b) has a higher affinity for oxygen than that of an adult (c) has a lower affinity for oxygen than that of the adult (d) its affinity for oxygen is the same as that of an adult.

Last Answer : (b) has a higher affinity for oxygen than that of an adult

The chemical potential for a pure substance is __________ its partial molal free energy. (A) More than (B) Less than (C) Equal to (D) Not related to

Description : The chemical potential for a pure substance is __________ its partial molal free energy. (A) More than (B) Less than (C) Equal to (D) Not related to

Last Answer : (C) Equal to