Class 10 > PYQ SCIENCE > 2011 > SET 1

2011

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Q2
Give an example of a phenomenon where Tyndall effect can be observed.

Q3
What is meant by biological magnification?

Q4
Explain with the help of a diagram, how we are able to observe the sunrise about two minutes before the Sun gets above the horizon.

Q5
How does the valency of elements vary
1-in going down a group, and
2-in going from left to right in a period of the periodic table?

Q6
In the modern periodic table, the element Calcium (atomic number = 20) is surrounded by elements with atomic numbers 12, 19, 21 and 38. Which of these elements has physical and chemical properties resembling those of Calcium and why?

Q7
(a) List any two disadvantages of using fossil fuels for the production of energy.
(b) Give two examples each of the following:
1-Renewable sources of energy.
2-Non-renewable sources of energy.

Q8
Describe any three ways in which individuals with a particular trait may increase in population

Q9
State the evidence we have for the origin of life from inanimate matter.

Q10
’What are fossils? What do they tell us about the process of evolution?

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