CLASS VIII SCIENCE CHAPTER – 5 Coal and Petroleum Assignment |
Q.1 Fill in the blanks:- |
(i) On heating in air, coal mainly produces ________ gas. |
(ii) ________ is an almost pure form of carbon. |
(iii) Coal tar is a mixture of about ________ substance.. |
(iv) Now a days ________, a petroleum product is used in place of ________ for metalling the roads. |
(v) ________ is obtained during the processing of wood to get coke. |
Q.2 What are natural resources? |
Q.3 Give three examples of natural and man-made material? |
Q.4 What are the two kinds of natural resources? Explain giving examples? |
Q.5 What are fossil fuels? Give three examples? |
Q.6 Write three uses of coal? |
Q.7 What is meant by carbonization? |
Q.8 Write two uses of coke? |
Q.9 Name four substances which are manufactured using products obtained from coal tar? |
Q.10 How is petroleum formed? |
Q.11 name three places in India where petroleum oil is found. |
Q.12 What is petroleum refining? |
Q.13 Write two uses of petrol, kerosene, diesel, paraffin wax and bitumen? |
Q.14 Why is CNG being used as a fuel for vehicles? |
Q.15 Explain why should we use fossil fuels only when absolutely necessary. |
Q.16 What is the full form of LPG and CNG? |
Q.17 What are the tips given by PCRA to save petrol and diesel? |
Q.18 Why is petroleum called black gold? |
Q.19 Give two advantages of natural gas as a fuel. |
Q.20 Explain why coal, petrol and diesel oil will be exhausted one day. |
Class 09 Atoms and Molecules Numerical Problem based on Law of chemical Combination Law of conservation of mass Law of constant proportion Empirical formula 1. If 10 grams of CaCO 3 on heating gave 4.4g of CO 2 and 5.6g of CaO, show that these observations are in agreement with the law of conservation of mass.(Based on Law of conservation of mass) Solution: Mass of the reactants = 10g ; Mass of the products = 4.4 + 6.6g = 10g Since the mass of the reactants is equal to the mass of the products, the observations are in agreement with the law of conservation of mass. 2. 1.375 g of cupric oxide was reduced by heating and the weight of copper that remained was 1.098g. In another experiment 1.179 g of copper was dissolved in nitric acid and the resulting copper nitrate was converted into cupric oxide by ignition . The weight of cupric oxide formed was 1.476 g. which law of chemical combinations does this data state? Solution: in first experiment: Copper oxide = 1....
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