CBSE Class 10 Science Solved Question Paper 2016, is available here. Students can download the complete paper from the link given at the end of this article.
Though the structure of this paper is wholly different from that released by the board for Borad Exams 2018, but the importance of questions asked in previous years’ exams cannot be ignored as the syllabus for Class 10 Science remains unaltered. So, studenst must practice the previous years’ papers to get a command over the important topics and prepare accordingly for the CBSE Board Exams 2018.
CBSE Class 10 New Exam Pattern 2017-2018
CBSE Class 10 Science Solved Question Paper 2016, contains:
- 36 question divided into two sections - A and B
- Simple and apt solution for each question
- Every solution framed on the basis of the CBSE Marking Scheme
- Neat and clean figures where required
Students need to practice CBSE Class 10 Science Solved Question Paper 2016, to check their preparedness and build confidence for the final exam.
CBSE Class 10 Science Syllabus 2017-2018
A few sample questions from the CBSE Class 10 Science Solved Question Paper 2016, are given below:
Q. List two functions of ovary of human female reproductive system.
Ans.
Ovary is also the source of female hormone like estrogen. Estrogen is required for the development of secondary sex characteristics in females.
Ova in female are produced by ovary through a process of oogenesis.
Q. An element 'X' belong to 3rd period and group 13 of the Modern Periodic Table.
(a) Determine the number of valence electrons and the valency of 'X'.
(b) What is the molecular formula of the compound formed when 'X' reacts with an element 'Y'? (atomic number = 8).
(c) Write the name and formula of the compound formed when 'X' combines with chlorine.
Ans.
Here, period number of element X is 3 and group number of element Y is 13.
Therefore, atomic number of element is 13 and its electronic configuration is 2, 8, 3.
(a) Number of valence electrons of element X is 3 and it has a tendency to lose 3 electrons so, its valency is 3.
(b) As, atomic number of element Y is 8 so, it electronic configuration is 2, 6 and its valency is (8 ‒ 6 =) 2. Therefore, molecular formula of the compound formed is X2Y3.
(c) The atomic number of chlorine is 17, so its electronic configuration is 2, 8, 7 and its valency is (8 ‒ 7=) 1. Hence, molecular formula of the compound is XCl3.
Element X is aluminium, so the name of the compound AlCl3 is aluminium chloride.
Q. Define evolution. How does it occur? Describe how fossils provide us evidences in support of evolution.
Ans.
Evolution is the gradual process of accumulation of adaptive changes in population’s genetic makeup through successive generations. Mutations produce sudden, discontinuous variations which accumulate in the gene pool. These random variations are acted upon by natural selection that favors, through differential reproduction, only those which confer survival and/or reproductive advantage to the individuals over others. Accumulation of these adaptive variations in lineages over generation makes them better adapted to existing environmental conditions. Further, reproductive isolation of populations of species by geographical and/or physiological barriers leads to formation of new species i.e. evolution.
Fossils are the preserved remains of ancient organisms and are formed by their burial, rot away of soft parts. Over time sediment builds over the top and press downs the buried remains. The hard bony skeleton of animals and woody parts of plants are preserved by mineralization with simultaneous transformation of sediment into rock due to pressure and chemical reactions. Thus, as one moves from lower to upper strata of these rocks, older fossils are found in lower strata while the recent one are found in upper strata. Respective location of fossils in different strata and the anatomy and physiology exhibited by them represent the evolutionary trend of different taxonomic groups and individual forms over different geographical periods. Further, transitional fossil organisms (carrying characters of two different present day groups; missing links or connecting links) provide proof for evolutionary relationship between different groups of organisms and thereby establishing evolutionary sequence.
Q. If you are asked to select a group of two vegetables, out of the following, having homologous structures, which one would you select?
(a) Carrot and radish
(b) Potato and sweet potato
(c) Potato and tomato
(d) Lady finger and potato
Ans.
(a)
Homologous structures are those structures that have the same origin but can perform same or different functions in different organisms.
Here, both carrot and radish are modifications of the root for food storage.
Q. To determine the approximate value of the focal length of a given concave mirror, you focus the image of a distant object formed by the mirror on a screen. The image obtained on the screen, as compared to the object, is always
(a) laterally inverted and diminished
(b) inverted and diminished
(c) erect and diminished
(d) erect and highly diminished
Ans.
(b)
When the object is at infinity then the image formed by concave mirror is at the focus of the screen placed in front of it.
The image formed will be real, inverted highly diminished in size.
Q. A student adds a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid. List two main observations that he/she must note in his/her notebook about the reaction that takes place. Also, write chemical equation for the reaction.
Ans.
Two important observations that must be noted when student adds a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid are:
1. Brisk effervescence is observed due to the release of CO2 from the reacting mixture.
2. Heat is released during the reaction.
Chemical equations for the reaction are:
NaHCO3 + CH3COOH → CH3COONa + CO2 (g) + H2O
Ca(OH)2 + CO2 → CaCO3 + H2O
Download the complete CBSE Class 10 Science Solved Question Paper 2016
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CBSE Class 10 Science Solved Question Paper 2017
CBSE Class 10 Science Sample Paper 2016-2018