Please refer to Sample Paper Class 10 Science Term 2 Set E with solutions provided below. We have provided CBSE Sample Papers for Class 10 Science as per the latest paper pattern and examination guidelines for Standard 10 Science issued by CBSE for the current academic year. The below provided Sample Guess paper will help you to practice and understand what type of questions can be expected in the Class 10 Science exam.

CBSE Sample Paper Class 10 Science for Term 2 Set E

Section – A

1. 1) An element ‘Z’ has four shells and same number of electrons in the first and fourth shell as well as second and third shell.
a) Identify its group and period.
b) Write the electronic configuration of the element.
c) What type bond will it form with the element ‘X’(2,8,6)
Answer. a) group 2 and period 4
b) 2,8,8,2
c) ionic bond

2. In any homologous series there is a gradation in physical properties but the chemical properties remain similar. Justify the given statement with valid reasons.
Answer. As the molecular mass increases in any homologous series, a gradation in physical properties is seen. This is because the melting and boiling points increase with increasing molecular mass. .But the chemical properties, which are determined solely by the functional group, remain similar in a homologous series

3.

a) Identify the glands A and B in the figure given above.
b) Write two functions of the secretions of these glands.
Answer. a) A-prostate gland, B-seminal vesicle
b) Sperms are in fluid form which makes their transport easier and this fluid also provide nutrition

4. Rahul noticed that buds in the notches along the leaf margin of a plant fall on the soil and develop, into new plants.
a) Identify the plant and the specific mode of asexual reproduction
b) List two advantages of this mode of propagation in plants
Answer. a) Bryophyllum, vegetative propagation
b) Bears flowers and fruits much earlier than plants produced from seeds, plants produced are genetically similar to parent plant or any other correct advantage

5 In the given Mendelian di hybrid cross 4 types of combinations were seen in the F2 generation. Identify and classify these types as parental types and new combinations

When two purebred rabbits, a male with black fur and a female with tan fur are crossed , all of the F₁ generation had tan fur. Identify the dominant and recessive trait .Justify your answer giving reason for this identification.
Answer. Parental types-round and yellow, wrinkled and green New combinations-wrinkled and yellow, round and green
                                        OR
Tan fur is dominant, while black fur is recessive.
Tan fur is the dominant trait, because it is expressed in the offspring of the cross. Black fur is the recessive trait, because it is hidden in the offspring of the cross.

6 How would the strength of magnetic field in a current carrying loop be affected if
a) the radius of the loop is reduced to half of its original radius?
b) strength of current through the loop is doubled?
                                                OR

P and Q shows the magnetic field lines of force between the poles of the magnet. Identify the poles A,B,C and D
Answer. a) The strength of magnetic field is doubled/increases
b) The strength of magnetic field increases two times/increases.
               OR
Fig P-unlike poles
Fig Q-like poles

7 Food web increases the stability of an ecosystem. Justify
                                                                        OR
State and explain any two possible consequences of elimination of decomposers from the earth.
Answer. Food web depicts a series of branching lines of food chain where many food chains are interlinked. If any one of the organism becomes endangered or extinct ,food chain offers alternative options for survival
                               OR
Increase in complex organic substances causes land and water pollution, may disturb the balance of ecosystem or any other logically correct reason.

Section – B

8 i. How and why does the atomic size of the elements vary as we move
a) from left to right in a period and b) down a group?
ii. How does the tendency of the elements to lose electrons change in the modern periodic table a) in a group and b) in a period?
Answer. (i) a. Atomic size decreases due to increase in nuclear charge
b. Atomic size increases due to increase in no. of shells
(ii) a. In a period it decreases and b) In a group it increases

9 Define the term isomers. Draw the structures of two isomers of butane. Explain why we cannot have isomers of first three members of alkane series
Answer. Definition of isomers
Structure of isomers of butane – NCERT textbook page no. 65 ,fig.4.8(b)
First three members of alkane do not have branched structure

10 Explain with suitable example how Mendel proved that traits are inherited independently.
Answer. Explanation of di hybrid crossing

or any other example

11 Show how would you join three resistors, each of resistance 9 ohm so that the equivalent resistance of the combination is (i) 13.5 ohm (ii) 6 ohm
Answer. Two 9 ohm resistors in parallel connected to one 9 ohm resistor in series

Two 9 ohm resistors in series connected to one 9 ohm resistor in parallel connection

1/R = 1/18 + 1/9 = 3/18
R = 6 ohm

12 Calculate the total cost of running the following electrical devices in the month of September, if the rate of 1 unit of electricity is Rs. 6.00
(i) Electric heater of 1000W for 5 hours daily
(ii) Electric refrigerator of 400W for 10 hours daily
Answer. P₁=1000 W=1000/1000 kW, t₁ = 5h
P₂ = 400 W = 400/1000kW, t₂ = 10h
No. Of days, n = 30
E₁ = P₁ x t₁ x n = 1 kW x 5h x 30 = 150 kWh
E₂ = P₂ x t₂ x n = 400 /1000 kW x 10hx30 = 120kWh
:. Total energy = (150 +120) kWh = 270 kWh
:: Total cost = 270 x 6 = Rs. 1620

13 (i) Write down the importance of ozone layer and mention how its formed.
(ii) Explain the causes of depletion of ozone layer
Answer. Protect us from harmful radiations of sun
Ozone is formed by combining diatomic oxygen molecule with one oxygen atom.
Depletion by chemicals like CFCs and Freon

Section – C

This section has 02 case-based questions (14 and 15). Each case is followed by 03 sub-questions (a, b and c). Parts a and b are compulsory. However, an internal choice has been provided in part c.

14 Whether an animal will become a male, a female, or a hermaphrodite is determined very early in development. Scientists have worked for hundreds of years to understand the sex-determination system. Environmental theories of sex determination, such as Aristotle’s, were popular until about 1900, when sex chromosomes were discovered. For most animals, however, sex is determined
chromosomally.
a) Give one example of an environmental factor that govern sex determination.(1)
b) Males are heterogametic, Why?
c) With the help of a flow chart determine genetically in human beings the sex of offspring if the sperm carrying X chromosome fertilizes the egg
                                                                                      OR
Male has 46 chromosomes and female has 46 chromosomes. Then why does not their offspring has 46 pairs of chromosomes which is obtained by fusion of male and female gametes?
Answer. a) Temperature at which fertilized eggs are kept
b) Males produce two types of gametes X and Y
c)

                                                                               OR
c) Gametes have half the number of chromosomes, thus ovum will have 23 and sperm will have 23.Fusion of these gametes restores 46 chromosomes

15 A solenoid is long helical coil of wire through which a current is run in order to create a magnetic field. The magnetic field of the solenoid is the superposition of the field due to the current through each coil. It is nearly uniform inside the solenoid and close to zero outside and is similar to the field of a bar magnet having a north pole at one end and a south pole at the other depending upon the direction of current flow.
The magnetic field produced in the solenoid is dependent on a few factors such as, the current in the coil, number of turns per unit length etc.
a) What decides the direction of magnetic field by a current carrying solenoid?
b) How can we compare a current carrying solenoid with a bar magnet?
c) How can we increase the strength of the magnetic field produced by a current carrying solenoid?
                                                                         OR
How can we make an electromagnet with the help of a solenoid?
Answer. a) Direction of flow of current through the solenoid
b) The magnetic field produced by a current carrying solenoid
is similar to the magnetic field produced by a bar magnet.
c) Strength of magnetic field can be increased by increasing current and increasing the number of turns
                                                                        OR
An electro magnet can be made by keeping a soft iron core inside a current carrying solenoid