CBSE
Worksheet
Class–VIII Science (Combustion and Flame)
a. oil b. electricity c. both a & b d. burning of wood
2. A fire extinguisher works on following principle/s :-
a. removing combustible substance
b. cooling the burning substance below ignition temperature
c. cutting off supply of air
d. both b & c
3. The dark zone of a candle flame is :-
a. region around the wick
b. base close to wick
c. middle region of flame
d. outer region of flame.
4. Incompletely burnt fuel releases a very poisonous gas that can be fatal if inhaled :-
a. carbon dioxide b. ozone c. carbon monoxide d. water gas
5. Match the column :-
a. Carbon dioxide i) also called gobar gas
b. Oxygen ii) highest calorific value
c. Hydrogen iii) gas essential for burning
d. Biogas iv) non pollutant vehicular fuel
e. CNG v) used in fire extinguisher
6. State whether the following statements are true or false :-
a. If ignition temperature is higher than room temperature, the fuel is considered good.
b. Combustion is an oxidation process.
c. If supply of oxygen is insufficient during combustion, carbon dioxide is formed instead of carbon monoxide.
d. Any combustion reaction not accompanied by flame is known as burning.
e. Body fuel like butter gives us more energy than others.
7. What is SPM? Which type of pollution it might cause?
8. Deforestation and excess burning of fossil fuels is leading to a global problem. Explain it.
9. Pick the odd word out of the following:
LPG, wax, kerosene, charcoal, bunsen burner.
10. Write the correct words by putting letters in correct sequence-
i) panetsouson ii) riversoco
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