» CBSE Science Practice Paper : Set XI : CBSE Sample Question Papers

16. State Ohm’s law. Draw a electrical circuit with a battery, Resistance, Bulb and a Key. If the resistance 0f the bulb is equal to that of the resistor, and the potential of battery is V, find the current drawn from the cell? 3
Answer :

17. What happens when
(i) ammonia gas is oxidised in presence of air at 1873 K in presence of Pt. gauze. (ii) nitric oxide is oxidised in presence of oxygen. (iii) ammonia reacts with concentrated hydrochloric acid.

OR
Complete and balance the following reactions :
(i) Na + H₂O—>
(ii) Zn + HC1 -> (iii) Fe₂O₃ +Al —> 3
Answer :

18. What is dispersion ? Which colour of light deviates more on passing through a prism ? When two prisms are placed together with one inverted and white light is passed, what will be the result ? 5
Answer :

19. Define calorific value of fuel. Why is calorific value of CH₄ higher than that of butane ?
The heat produced on complete combustion of 10 g of fuel could raise the temperature of 2 kg of water from 20^° to 70^°C. Calculate the calorific value of the fuel, if the specific heat of capacity of water were 4.2 J/g^°C. Assume that the heat taken by the container is negligible.

OR
How is biogas prepared ? Give its composition.
The calorific value of biogas is 40 kJ/g. Calculate amount of biogas required tp produce 1000 kJ of energy. 2+3
Answer :

20. What are Geostationary satellites ? How are they useful to mankind ? Derive the height at which the satellite can be serving as Geostationary satellite ? 5
Answer :

Section - B

21. What is a retrovirus ? !
Answer :

22. Name the procedure used in the working of artificial kidney. 1
Answer :

23. Why is SA node called pacemaker of the heart ? 1
Answer :

24. How does hydra reproduce ? Name another organism that reproduces by the similar method. 2
Answer :

25. Name two National Parks and two Sanctuaries of our country. 2
Answer :

26. Name the scientist who discarded Lamarck’s theory of inheritance of acquired characters ? How did he disprove of the theory ? 3
Answer :

27. Explain the various factors that affect the rate of photosynthesis in plants. 3
Answer :

28. Describe the mechanism of excretion in Amoeba. 3
Answer :

29. Name the type of non-biodegradable pollutant that can lead to harmful changes in the genes. Mention the measures that are to be taken to control this pollution. 3
Answer :

30. Explain with a diagram, the human male reproductive system. Mention the functions of human ovary.

OR
Explain with a diagram, the human female reproductive system. Mention the functions of human testis. 5
Answer :