6.4 MULTIPLE CHOICE QUESTIONS:(MCQ’s)
1. __________ is a chemical process in which a substance reacts with oxygen to give off heat.
a) Heat b) Oxidation c) Combustion d) Reduction
2. The lowest temperature at which a substance catches fires is known as its _______.
a) Ignition Temperature b) Oxidation c) Combustion d) None of these
3. A substance which disrupts the contact between air and the fire is called ______.
a) Matches b) Extinguisher c) Oxidiser d) None of these
4. The innermost zone of unburnt vapours.
a) Blue zone b) Brown Zone c) Red zone d) Black zone
5. The amount of heat energy produced on complete combustion of 1kg of a fuel is called _________.
a) Calorific value b) Heat value c) Energy value d) None of these
6. Burning of charcoal in a closed room will produce __________.
a) Carbon dioxide b) Oxygen c) Nitrogen d) Carbon monoxide
7. Combustion is a ____________process
a) Chemical b) Physical c) Neutral d) None of these
8. One product of Combustion is ___________.
a) Carbon dioxide b) Steam c) Nitrogen d) None of these
9. Which is the best domestic fuel?
a) Kerosene b) LPG c) CNG d) none of these
10. What is the colour of the LPG flame?
a) Red b) Brown c) Blue d) Black
11. Name two fuels which are used in industries.
a) Coal and Diesel b) Wood,Petrol c) Kerosene, CNG d) CNG,Coal
12. The substance in which combustion takes place are called ___________substances .
a) Combustible b) Combustors c) Burning d) None of these
13. Characteristics of a good fuel.
a) Give black flame b) Costly c) Should be cheap d) All of the above
14. The oxides of sulphur and nitrogen dissolve in rain water to form _________.
a) Bases b) Acids c) Gases d) None of above
15. The hottest zone of the flame is _____________.
a) Outermost zone b) Inner zone c) Middle zone d) Blue zone
Answers :
1. a) 2. c) 3. b) 4. a) 5. d) 6. a) 7. b) 8. d)
9. c) 10. a) 11. b) 12. d) 13. b) 14. c) 15. a) .