10th Science Periodic Test I A (2018-19)

10th Science Periodic Test I A (2018-19)

School Name: Venkateshwar Global School, Sector 13, Rohini, Delhi 110085 India
Time: 1.5 hour
M.M: 40
Class: X
Subject code: 086
Date: 16/07/2018

All questions are compulsory

Question: 1. What will happen to a plant if its xylem is removed? (1)

Question: 2.What do you mean by precipitation reactions? Explain giving example. (1)

Question: 3. What happens to the image distance in the eye when we increase the distance of an object from the eye? Why? (1)

Question: 4. Explain the reddish appearance of sun at sunrise and sunset. (2)

Question: 5. The absolute refractive indices of two media ‘A’ and ‘B’ are 2 and 1.5 respectively. If the speed of light in medium ‘B’ is 2×10²m/s, calculate the speed of light in (2)

1. Vacuum,
2. Medium ‘A’.

Question: 6. What is ascent of sap? (2)

Question: 7.Translate the following statements into chemical equations and balance them: (2)

1. Copper (II) burns in the presence of oxygen gas to form copper oxide.
2. Silver nitrate reacts with sodium chloride to form silver chloride and sodium nitrate.

Question: 8. Quicklime when dissolved in water gives compound ‘A’ which is used in white-washing. Compound A reacts with CO₂ to form a white colored compound of ‘B’. Identify A and B. Also write balance equation involved in the conversion of A to B. (2)

Question: 9. Mention the major events during photosynthesis. (3)

Question: 10. Two solutions X and Y have pH values of 3.0 and respectively. (1+2)

1. Which of these will turn phenolphthalein solution to pink?
2. Write any 2 applications of pH in our daily life and explain them.

Question: 11. Give reasons: (3)

1. Plants look preen.
2. Nutrition is necessary for an organism.
3. We boil the leaf in alcohol when we are testing it for starch.

Question: 12. A 2 cm high object is placed at a distance of 32 cm from a converging mirror. The image is real and 3 cm in size. Find the focal length of the mirror and the position and nature of the image formed? (3)

Question: 13 (3+2)

1. What is myopia? Write a cause for the development of this defect. With the help of ray diagrams, show the defect and how it can be correct using spectacles having appropriate lens.
2. What do you understand by dispersion of light? Which of the following show dispersion of light: rectangular glass slab of glass prism, and why?

Question: 14. (2+3)

1. Define double circulation.
2. Trace the path of blood circulation in humans.

Question: 15. Answer the following question: (2+2+1)

1. Distinguish between acids and bases on the basis of their reactions with metal carbonates and write balanced equations to support your answer.
2. Why does distilled water not conduct electricity, whereas rain water does?
3. What are olfactory indicators?