CBSE Class-10 Exam 2016 : Delhi Scheme
Question Paper, Science
CBSE Class-10 Exam 2016 : Science
SUMMATIVE ASSESSMENT - II
Time allowed : 3 hours ]
[ Maximum marks : 90
1. Write the next homologue of each of the following :
(i) C2 H4
(ii) C4 H6
2.Name the part of Bryophyllum where the buds are produced for vegetative propagation.
3. List two natural ecosystems.
4. State two positions in which a concave mirror produces a magnified image of a given object. List two differences between the two images.
5. List four advantages of properly managed watershed management.
6. Explain giving example where active involvement of local people lead to efficient management of forest.
7. What are covalent compounds? Why are they different from ionic compounds? List their three characteristic properties.
8. When ethanol reacts with ethanoic acid in the presence of conc. H2 SO4 , a substance with fruity smell is produced. Answer the following :
(i) State the class of compounds to which the fruity smelling compounds belong. Write the chemical equation for the reaction and write the chemical name of the product formed.
(ii) State the role of conc. H2 SO4 in this reaction.
9. Calcium is an element with atomic number 20. Stating reason answer each of the following questions :
(i) Is calcium a metal or non-metal?
(ii) Will its atomic radius be larger or smaller than that of potassium with atomic number 19 ?
(iii) Write the formula of its oxide.
10. An element ‘M’ with electronic configuration (2, 8, 2) combines separately with (NO3 )- , (SO4)- and (PO4 )3- radicals. Write the formula of the three compounds so formed. To which group and period of the Modern Periodic Table does the elements ‘M’ belong? Will ‘M’ form covalent or ionic compounds? Give reason to justify your answer.
11.How do organisms, whether reproduced asexually or sexually maintain a constant chromosome number through several generations? Explain with the help of suitable example.