"Om Sai Ram"
Spectrum
Classes
Class X
Science
Time:1:30Hrs
Max
Marks:50
Instructions:
(i)
All questions are compulsory.
(ii)
There are 20 questions in total. Questions 1 to 5 are very short answer type
questions
and
carry one marks each.
(iii)
Questions 6 to 11 carry two marks each, questions 12 to 16 carry three marks each
and
questions 17 value based question 3
marks and 18 to 20 carry five marks
Q.1
Give one example of a unisexual flower.
Q.2 Difference between Mendeleev periodic law
& modern Periodic law .
Q.3 Which type of mirror is usually used as a
rear-view mirror in motor cars & Why ?
Q.4 List two reasons why
carbon forms large number of compounds and are
poor
conductors of electricity?
Q.5 Define one dioptre of power of a lens? Explain
why? ‘Danger’ signal are red in colour.
Q.6 Draw the electron dot
structure of the gas molecule which is liberated when zinc metal is treated
with aqueous NaOH solution.
Q.7 Refractive index of two
material medium X and Y are 1.3 and 1.5 respectively. In which of the two, the
light would travel faster?
Q.8 List two differences
between acquired and inherited traits.
Q.9 What is meant by power
of accommodation of the eye? How is it related
to
the focal length of the eye lens?
Q.10 “Fossils are related to
evolution”, justify this statement. Give the two ways by which age of the
fossils can be estimated?
Q.11 Light enters from air into
diamond which has a refractive index of 2.42.
Calculate the speed of light in diamond. The
speed of light in air is 3.0´10
8
m/s.
Q.12 Find the position, nature and size of the image formed by a convex
lens of focal
length 12 cm of an object 5 cm high placed at a
distance 20 cm from it.
Q.13How can you show that if a ray enters a
rectangular glass slab obliquely and
emerges from
the opposite face, the emergent ray is parallel to the incident ray? How can
you show that if a ray enters a rectangular glass slab obliquely and
emerges from the opposite face, the emergent ray
is parallel to the incident ray?
Q.14 Two elements with
symbol X (atomic no. 11) and Y (atomic no. 13) are placed in the III period of
the modern periodic table -
(i)
Which amongst the two has more metallic character?
(ii)
Calculate the valency of each element.
(iii)
Element ‘Y’ is smaller than ‘X’ in terms of atomic size. Is the
statement
true, justify?
Q.15
State how would you distinguish between Acetic acid and Ethanol in your laboratory.
Give chemical equation of the reactions shown by them. Write the chemical
equations involved.
Q.16
Explain with equation (a) Saponification (b) Esterification (c) Hydrogenation
Q.17 Ethanol, commonly called as alcohol is an
excellent solvent, is used in medicines and
is an important chemical compound involved in
synthesis of many chemical compounds.
However in spite of its benefits to man, its
impact on social behaviour has always been
questioned. Media has often show abnormal
behaviour of people while drunk. It is
considered as a curse in the lives of those who
are addicted to alcohol – ‘Alcoholic’
people are not only lowering their metabolism and
affecting Central Nervous System,
they are also a threat to the lives of others.
Anger and rude behaviour are some of its
ill effects.(i) Comment on the statement –
‘Should production of alcohol should be banned’,
give three valid reasons to justify.
(ii) As a student what initiative would you take
in the common concern of ‘Save
Life, Do not Drink’. Give two suggestions.
Q.18 ‘Sania and Shreya’ are best friends and
study in grade 4, recently, Sania has been
facing difficulty in reading the black-board text
from the last desk. Shreya is little
uncomfortable and wonders why sania avoids
sitting on the last desk. On observation
she found that sania often carries junk food in
her lunch. Shreya has started sharing
her lunch – full of green vegetables and fruits
with her. Sania is now better and has
also started taking a ‘balanced diet’.
(i) Name the eye defect Sania is suffering from?
(ii) What are the two possible deformities
related to her eye defect?
(iii) What value is shown by Shreya and Sania?
Q.19 Study the ray diagram given below and answer
the following questions –
(i) State the type of
lens used in the figure.
(ii)
List two properties of the image formed.
(iii)
In which position of the object will the magnification be -1?
Q.20
a) Identify the parts the 1, 2, 3 and 4 of the diagram given below. b) List two
changes that can be observed in the flower after fertilization
