One kg of carbon for theoretically complete combustion requires
__________ kg of air.
(A) 11.5
(B) 0.5
(C) 23
(D) 12

1 Answer

Answer :

(A) 11.5

Related questions

Description : Stoichiometric combustion of 12 kg of carbon requires __________ of oxygen. (A) 1kg mole (B) 22.4 Nm3 (C) 32 kg (D) All (A), (B) and (C)

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

Description : Oxygen required for theoretically complete combustion of 1 Nm3 methane is __________ Nm3 . (A) 2 (B) 4 (C) 6 (D) 1

Last Answer : (A) 2

Description : One kg of carbon requires 4/3 kg of oxygen and produces __________ kg of carbon monoxide gas.  A. 8/3  B. 11/3  C. 11/7  D. 7/3

Last Answer : Answer: D

Description : One kg of carbon monoxide requires __________ kg of oxygen to produce 11/7 kg of carbon dioxide gas.  A. All  B. 4/7  C. 11/4  D. 9/7

Last Answer : Answer: B

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

Description : A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) ... a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Last Answer : (D) None of these

Description : Dry air required to burn 1 kg of carbon completely may be around __________ kg. (A) 11 (B) 2 (C) 20 (D) 38

Last Answer : (A) 11

Description : Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to ... coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

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

Description : About __________ Nm3 of air will be required for the complete combustion of 2Nm3 of CO. (A) 2 (B) 3 (C) 4 (D) 5

Last Answer : (D) 5

Description : Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air. (A) Wet bulb (B) Dry bulb (C) Saturation (D) Dew point

Last Answer : Option A

Description : 1 kg of wood contains 15% moisture and 5% hydrogen by weight. How much water is evaporated during complete combustion of 1kg of wood? a) 0.6 kg b) 200 g c) 0.15 kg d) none of the above

Last Answer : b)200 g

Description : Theoretical volume of oxygen required for complete combustion of 1Nm3 of acetylene, in oxy-acetylene welding is __________ Nm3. (A) 0.5 (B) 1 (C) 1/3 (D) 2.5

Last Answer : Option D

Description : The theoretically correct air fuel ratio for petrol engine is of the order of a.6 : 1 b. 9 : 1 c. 12 : 1 d. 15 : 1

Last Answer : Answer d. 15:1

Description : Momentum of electron having mass 9.1 × 10-31 kg and velocity 2.0 × 107 is A. 1.91 × 10-23 B. 2.34 × 10-23 C. 3.11 × 10-19 D. 7.88 × 10-34

Last Answer : 1.91 × 10-23

Description : Air/fuel ratio by weight for combustion of methane with theoretical quantity of air will be about (A) 9 : 1 (B) 17 : 1 (C) 23 : 1 (D) 29 : 1

Last Answer : (B) 17 : 1

Description : An organic compound contain 69% carbon and 4.8% hydrogen, the remaining being oxygen. Calculate the masses of carbon dioxide and water produced when 0.20g of this substance is subjected to complete combustion.

Last Answer : Calculation of mass of CO2 produced: Mass of compound =0.20g %C =12 x C 69=12*mass of CO2 formed*100/44*0.2 Mass of CO2 formed =69*44*.2/12*100 = 0.506g Similarly, % H =2* mass of H2Oformed*100/18* ... compound 4.8=2* mass of H2Oformed*100/18* 0.2 Mass of H2Oformed =4.8*18*0.2/2*100 =0.0864g

Description : Catalyst used in the 'catalytic converter' employed in automobile exhaust line for complete combustion/oxidation of carbon monoxide, nitrogen oxides and hydrocarbons is (A) Alumina (B) Platinum (C) Vanadium pentoxide (D) Iron oxide

Last Answer : Option B

Description : Evaporation of 1kg of water from a solution in a single effect evaporator requires about __________ kg of steam. (A) 0.4 - 0.6 (B) 1-1.3 (C) 1.8-2 (D) 2 - 2.4

Last Answer : (B) 1-1.3

Description : Calculate the attenuation constant of a conductor of conductivity 200 units, frequency 1M radian/s in air. a) 11.2 b) 1.12 c) 56.23 d) 5.62

Last Answer : a) 11.2

Description : Though, theoretically the adsorption & desorption isotherms is expected to coincide but sometimes at least a part of the isotherms does not coincide and this phenomenon is known as adsorption hysteresis. In such ... (B) Higher than (C) Same as (D) Either same or higher than

Last Answer : (A) Lower than

Description : In case of parallel flow heat exchanger, the lowest temperature theoretically attainable by the hot fluid is __________ the outlet temperature of the cold fluid. (A) Equal to (B) More than (C) Less than (D) Either more or less than (depending upon the fluid)

Last Answer : (A) Equal to

Description : A mass of 1 kg is attached to two identical springs each with stiffness k = 20 kN/m as shown in the figure. Under frictionless condition, the natural frequency of the system in Hz is close to * 1 point (A) 32 (B) 23 (C) 16 (D) 11

Last Answer : (A) 32

Description : In what ratio must a person mix three kinds of Oats costing him Rs 1.20,Rs 1.44 and Rs 1.74 per Kg so that the mixture may be worth Rs 1.41 per Kg? A)11:77:7 B) 11:45:7 C)25:45:8 D) 27:23:6

Last Answer : A)11:77:7

Description : One kg of carbon produces __________ kg of carbon dioxide.  A. 3/7  B. 7/3  C. 11/3  D. 3/11

Last Answer : Answer: C

Description : Which of the following can be calculated theoretically using steam table and Dalton's law of partial pressure; if the relative humidity and dry bulb temperature of moist air is known? (A) Dew point (B) Humidity ratio (C) Wet bulb temperature (D) None of these

Last Answer : (C) Wet bulb temperature

Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature

Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs

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

Description : Two students appeared at an examination. One of them secured 18marks more than the other and his marks was 72% of the sum of their marks. What are the marks obtained by them? a) 12.5,23.3 b) 26.7,16.0 c) 13.3,14.2 d) 11.45, 29.45 e) 29.8,15.4 

Last Answer : Answer: D  Let the marks secured by them be x and (x + 18)  Then sum of their marks = x + (x + 18) = 2x + 18  Given that (x + 18) was 72% of the sum of their marks  =>(x+18) = 72/100(2x+18)  => ... 11x = 126 x = 11.45  Then (x + 18) = 11.45 + 18 = 29.45  Hence their marks are 11.45 and 29.45

Description : Air/gas ratio for complete combustion will be the highest for (A) LPG (B) Gobar gas (C) Coke oven gas

Last Answer : (A) LPG

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

Description : Which of the following would require maximum amount of % excess air for complete combustion? (A) Coke oven gas (B) Furnace oil (C) Pulverised coal (D) Lump coal (fixed on chain grate)

Last Answer : (D) Lump coal (fixed on chain grate)

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

Description : The main function of primary air in pulverised coal fired burner is to (A) Burn CO to CO2 (B) Dry and transport the coal (C) Have proper combustion by supplying it around the burner (D) Preheat the tertiary air used for complete combustion of CO to CO2

Last Answer : (B) Dry and transport the coal

Description : Supply of excess air for complete combustion of fuel is necessitated to facilitate (A) Its thorough mixing with air (B) Attainment of chemical equilibrium (C) Attainment of high temperature (D) None of these

Last Answer : (A) Its thorough mixing with air

Description : The ratio of the ages of Bala and Babu is 13: 11. The total of their ages is 3.6decades. The proportion of their ages after 0.95decades will be [1 Decade = 10 years] a) 24:23 b) 12:11 c) 27:24 d) 29:26

Last Answer : D Let, Bala’s age = 13A and babu’s age = 11A Then 13A + 11A = 36 A = 1.5 Bala’s age = 19.5years and Babu’s age = 16.5 years Proportion of their ages after 9.5 is = (19.5+9.5) : (16.5 + 9.5) = 29 : 26

Description : A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Last Answer : (B) 11.77 kPa

Description : Chenna dhal is now being sold at Rs. 70 a kg. Last month, is rate was Rs. 80 per kg. By how much percent should a family reduce its consumption so as to keep the expenditure fixed? a)12.5 b)21.8 c)23 d)18

Last Answer : Answer: A  Let a family's monthly consumption of chenna dhal be x kg.  To keep the expenditure fixed,  their consumption for this month should be 70x/80 = 7x/8.  Reduction in consumption = x/8 = 12.5% of x

Description : The theoretically correct air fuel ratio of a petrol engine is of the order of A. 6:1 B. 10:1 C. 15:1 D. 20:1

Last Answer : ANSWER : C

Description : Presence of free moisture in coal is most disadvantageous during (A) Its pulverisation (as it requires more power) (B) Combustion of fire slacks on the grates (C) Handling (e.g. when emptying wagons) (D) None of these

Last Answer : (A) Its pulverisation (as it requires more power)

Description : Combustion of pulverised fuel (A) Requires larger combustion chamber than rich gaseous fuel (B) In a metallurgical furnace does not contaminate the product in the furnace by ash from fuel (C) Suppresses the discharge of fine dust and grit into atmosphere (D) All (A), (B) and (C)

Last Answer : (A) Requires larger combustion chamber than rich gaseous fuel

Description : Incomplete combustion of a fuel is characterised by the high __________ in the flue gas. (A) Smoke (B) Temperature (C) Oxygen (D) Carbon monoxide

Last Answer : (D) Carbon monoxide

Description : __________ resistance is not involved in the combustion of a carbon particle. (A) Gas film (B) Ash (C) Chemical reaction (D) None of these

Last Answer : (B) Ash

Description : 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50'. What number is missing? -Riddles

Last Answer : 22

Description : The air requirement of a petrol engine during starting compared to the theoretical air requirement for complete combustion is A. more B.unpredictable C. same D. less

Last Answer : ANSWER : D

Description : The air requirement of a petrol engine during starting compared to theoretical air required for complete combustion is a. more b. less c. same d. may be more or less depending on engine capacity

Last Answer : ANSWER b. less

Description : An atom of an element with mass number 23 and atomic number 11 will have- (1) 11 neutrons, 12 protons and 11 electrons (2) 11 protons, 12 neutrons and 11 electrons (3) 11 protons, 12 electrons and 11 neutrons (4) 23 protons and 11 electrons

Last Answer : (2) 11 protons, 12 neutrons and 11 electrons

Description : Find the flux contained by the material when the flux density is 11.7 Tesla and the area is 2 units. a) 23.4 b) 12.3 c) 32.4 d) 21.3

Last Answer : a) 23.4

Description : When did John Keats die? A. 11 May 1838 B. 12 March 1833 C. 23 February 1821 D. 19 August 1825

Last Answer : 23 February 1821

Description : Refer to problem # 11. Determine the force that accelerates if to 12 m/s^2. horizontally along frictionless plane.  A. 2474.23 N  B. 2574.23 N  C. 3474.23 N  D. 2374.23 N Formula : M = wk / g F = ma /k

Last Answer : 2474.23 N