Q.1. Name the unit in which the calorific value of a fuel is expressed.
A. Kilo joule per kg (kJ/kg)
B. Kilo pascal (kPa)
C. Hertz (Hz)
D. Kilo watt hour (kWh)
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A. Kilo joule per kg (kJ/kg)
Q.2. Which zone of a flame does a goldsmith use for melting gold and silver?
A. Innermost zone.
B. Outermost zone.
C. Middle zone.
D. Any zone.
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B. Outermost zone.
Q.3. "It is difficult to burn a heap of green leaves but dry leaves catch fire easily." Choose the correct statement which explains the reason:
A. Ignition temperature of dry leaves are higher compared to green leaves.
B. Ignition temperature of green leaves are higher compared to dry leaves.
C. Given statement is wrong. Both dry as well as green leaves both have same ignition temperature.
D. Given statement is wrong. Green leaves catches fire more easily as compared to dry leaves.
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B. Ignition temperature of green leaves are higher compared to dry leaves.
Q.4. Which of the below are correct example of combustion?
I. Rusting of Iron.
II. Production of heat and light by Sun.
III. Burning of magnesium ribbon.
IV. Digestion of food.
A. Only I ,III and IV.
B. Only II and III.
C. Only III and IV.
D. All of the above.
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A. Only I ,III and IV.
Q.5. In an experiment 4.5 kg of a fuel was completely burnt. The heat produced was measured to be 180,000 kJ. What is the calorific value of the fuel?
A. 40000 kJ/kg
B. 810000 kJ/kg
C. 40000 kg/kJ
D. 810000 kg/kJ
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A. 40000 kJ/kg
Total mass of fuel = 4.5 kg
Heat produced by burning the given mass of fuel = 180,000 kJ.
We know that calorific value of fuel =Heat Produced /Mass Burnt =180,000 KJ /4.5 Kg.
Hence, the calorific value of the given fuel = 40,000 kJ/kg
Total mass of fuel = 4.5 kg
Heat produced by burning the given mass of fuel = 180,000 kJ.
We know that calorific value of fuel =Heat Produced /Mass Burnt =180,000 KJ /4.5 Kg.
Hence, the calorific value of the given fuel = 40,000 kJ/kg
Q.6. Which of the following statement are correct?
A. Different substances catch fire at different temperatures.
B. A combustible substance cannot catch fire or burn as long as its temperature is lower than its ignition temperature.
C. Combustion can take place even in absence of air.
D. Inflammable substances have very high ignition temperature.
I. Only A and B.
II. Only C and D.
III. Only A, B and D.
IV. All of the above.
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I. Only A and B.
Q.7. The job of a fire extinguisher is
A. to cut off the supply of air.
B. to bring down the temperature of fuel.
C. to eliminate the burning fuel.
D. Both A and B
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D. Both A and B
Q.8. Which of the below fuel is considered as ideal fuel?
A. Petroleum.
B. CNG.
C. Coal.
D. None of the above.
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D. None of the above.
[CTET Sep 2015]
Q.9. Which fuel has the highest calorific value from among the following?
A. Coal
B. Petrol.
C. Diesel.
D. Hydrogen.
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D. Hydrogen.
[CTET Sep 2015]
Q.10. A teacher places a lighted candle on the table in the classroom. He later covers it with a jar.
I. The candle stops burning after some time.
II. Air is required for keeping the candle burning.
III. Oxygen is required for keeping the candle burning.
Of the above three statements:
A. Only statement I is an observation.
B. Statement I and II are observations.
C. All the statements are observations.
D. All the statements are inferences.
[CTET Sep 2014]
Q.11. In which of the following units is the calorific value of fuels generally expressed?
A. Calories per gram.
B. Kilocalories per kilogram.
C. Joules.
D. Kilojoules per kilogram.
[CTET Sep 2014]
Q.12. Which of the following commonly used fuels has maximum calorific value?
A. Compressed Natural Gas (CNG).
B. Diesel.
C. Liquefied petroleum gas (LPG).
D. Petrol.
[CTET 2012]
Q.13. When CNG or LPG undergoes complete combustion, the products formed are :
A. CO2 Only.
B. CO2, CO and H2O.
C. CO2 and H2O.
D. CO2, SO2 and H2O.
[CTET 2012]
Q.14. Given below are a few chemical processes:
A. Rusting of Iron.
B. Burning of a candle..
C. Respiration.
D. Photosynthesis.
Which two of these represent slow combustion?
1. B and C.
2. B and D.
3. D and A.
4. A and C.
[CTET 2012]
Q.15. The gas which forms carboxy-hameoglobin in the blood, causing suffocation is
A. Carbon dioxide.
B. Chlorofluorocarbon.
C. Carbon monoxide.
D. Nitrogen.
[CTET 2012]
Q.16. The calorific value of a fuel whose 1.5 kg of mass produces 67,500 kJ of heat on burning completely will be
A. 45,000 kJ/kg
B. 30,000 kJ/kg
C. 1,01,250 kJ/kg
D. 1,01,250 kg/J
I. The candle stops burning after some time.
II. Air is required for keeping the candle burning.
III. Oxygen is required for keeping the candle burning.
Of the above three statements:
A. Only statement I is an observation.
B. Statement I and II are observations.
C. All the statements are observations.
D. All the statements are inferences.
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A. Only statement A is an observation.
[CTET Sep 2014]
Q.11. In which of the following units is the calorific value of fuels generally expressed?
A. Calories per gram.
B. Kilocalories per kilogram.
C. Joules.
D. Kilojoules per kilogram.
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D. Kilojoules per kilogram.
[CTET Sep 2014]
Q.12. Which of the following commonly used fuels has maximum calorific value?
A. Compressed Natural Gas (CNG).
B. Diesel.
C. Liquefied petroleum gas (LPG).
D. Petrol.
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C. Liquefied petroleum gas (LPG).
[CTET 2012]
Q.13. When CNG or LPG undergoes complete combustion, the products formed are :
A. CO2 Only.
B. CO2, CO and H2O.
C. CO2 and H2O.
D. CO2, SO2 and H2O.
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C. CO2 and H2O.
[CTET 2012]
Q.14. Given below are a few chemical processes:
A. Rusting of Iron.
B. Burning of a candle..
C. Respiration.
D. Photosynthesis.
Which two of these represent slow combustion?
1. B and C.
2. B and D.
3. D and A.
4. A and C.
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4. A and C.
[CTET 2012]
Q.15. The gas which forms carboxy-hameoglobin in the blood, causing suffocation is
A. Carbon dioxide.
B. Chlorofluorocarbon.
C. Carbon monoxide.
D. Nitrogen.
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C. Carbon monoxide.
[CTET 2012]
Q.16. The calorific value of a fuel whose 1.5 kg of mass produces 67,500 kJ of heat on burning completely will be
A. 45,000 kJ/kg
B. 30,000 kJ/kg
C. 1,01,250 kJ/kg
D. 1,01,250 kg/J
Click here for answer
A. 45,000 kJ/Kg
Total mass of fuel = 1.5 kg
Heat produced by burning the given mass of fuel = 67,500 kJ.
We know that calorific value of fuel = =Heat Produced /Mass Burnt =67500 kJ / 1.5 kg
Hence, the calorific value of the given fuel = 45,000 kJ/kg
Total mass of fuel = 1.5 kg
Heat produced by burning the given mass of fuel = 67,500 kJ.
We know that calorific value of fuel = =Heat Produced /Mass Burnt =67500 kJ / 1.5 kg
Hence, the calorific value of the given fuel = 45,000 kJ/kg
To Read notes on Combustion and Flame click here.
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