Q. 1. Which one of the following gases is used in combustion

(a) Hydrogen        (b) Oxygen            (c) Nitrogen                (d) Carbon dioxide

Q.2. Which of the following is not a fossil fuel

(a) Coal            (b) Petroleum               (c) Natural gas                (d) Water gas

Q.3. Substances that catch fire are called

(a) acids      (b) bases                      (c) combustible              (d) burners

Q.4. The SI unit of the calorific value of a fuel is:-

A. N/kg               B. kJ/kg                    C. KW/kg                   D. J/kg

Q.5. The color of the outer zone of a candle flame is:-

A. orange                B. blue                   C. red                            D. yellow

Q.6. Water cannot be used as a fire extinguisher to put out –

A. Burning charcoal                  B. Burning cloth                 C. Burning oil                D. Burning wood

Q.7. Which of the following factors are essential to ignite a fire

A. Heat                        B. Fuel                                C. Air (oxygen)                     D. All of these

Q.8. Which fuels are used for running automobiles

a. Wood b Coal    c. Diesel d Charcoal

Q.9. Fuel may be-

a. Solid b. Liquid     c. Gas d. All of these

Q.10.The lowest temperature at which a substance catches fire is called its-

a) Boiling point b. Melting point c. Ignition temperature d. Critical temperature

Q.11. Which one of the following is non-combustible

a. Stone piece b. Paper  c. Straw d. Matchsticks

Q.12. Fire extinguisher-

a. Cut off the supply of air b. Bring down the temperature of fuel c. Both (a) and (b)       d. None of these

Q.13. Rapid combustion is

a. When gas burns, it produces heat and light

b. When material suddenly burst into flames

c. When there is the evolution of heat

d. None of these

Q.14. Acid rain contains mainly

(a) oxygen and nitrogen gas    (b) fluorine and chlorine gas    (c) magnesium oxide (d) nitrogen oxide and sulfur dioxide

Q.15.Which zone represents the partial combustion in a candle flame

(a) Outer zone                     (b) Middle zone                       (c) Inner zone                         (d) Lower zone

Q.16. Burning coal in a closed room will produce

(a) nitrogen oxides                (b) carbon dioxide                      (c) carbon monoxide                (d) oxygen

Q.17. Which is a non-combustible substance

(a) Wood                          (b) Paper                                        (c) Iron nails                          (d) Straw

Q.18.Out of these, which is able to control fires

(a) NH3                   (b) H2                                   (c) CO2                                  (d) F2