Dwarka International School
Sector-12, Dwarka, New Delhi-110078
SA-1(Science) CLASS-8
{SAMPLE-PAPER}
M.M: 90 Marks
Time: 3 hours
GENERAL INSTRUCTIONS:
1. The paper is divided into three sections.
Sec A (Physics-29 marks), Sec-B( Biology-33 marks), Sec-C ( Chemistry-29 marks).
2. Marks of each question are written in front of them.
3. All questions are compulsory.
4. There is an internal choice in Q.No.8 of Sec-A, Q.No. 8 and 9 of Sec-B, Q. No.7 and 8 of Sec-C.
SECTION A-PHYSICS(29 Marks)
1. Choose the correct answer for the followings:(1X4= 4 Marks)
i. Atmospheric pressure ___________ with the altitude.
a) Remains same
b) Increases
c) Decreases
d) None of these
ii. On which of the following the force of friction doesn’t depends:
a) Mass
b) Nature of surface
c) Area
d) All of the these
iii. Which of the following type of friction has maximum magnitude:a) Static
b) Limiting
c) Sliding
d) Rolling
iv. The force acting between the Earth and the Moon is:a) Gravitational
b) Magnetic
c) electrostatic
d) frictional force
2. Read the passage given below carefully :(1+2= 3 Marks)
“Rohan has chosen the deep sea diving as one of his extracurricular activity during the summer
vacation. On one fine day he was ready with his guide for diving. His guide advised him wear a
special suit. He followed his advice but he was not sure how will it be helpful for him.”
On the basis of above passage answer the following questions:a) Was the advice of his instructor correct?
b) Can you help the Rohan to come out of this dilemma?
3. Differentiate between:( any two)
(2X2= 4 Marks)
a) Contact and non contact force.
b) Static friction and Kinetic friction.
c) Friction and drag.
4. Calculate the resultant force in each of the following:2 Marks
a)
50 N
20 N
10 N
b)
40 N
10 N
40 N
20 N
30 N
30 N
60 N
5. Calculate the amount of force required to exert a pressure of 100 Pascal by an object with surface
area of 2 m2.
2 Marks
6. Suppose if a bucket of soap solution is spread on a marble floor then it would be easier or difficult
for you to walk on that floor? Explain your answer.
3 Marks
7. Give reason for the followings:- ( any two)
( 2X3= 6 Marks)
a) Astronauts wear specially designed space suit.
b) Now a days bags are provided with rollers.
c) Iron nails are made pointed.
8. a) Draw the graph between the friction and applied force.
5 Marks
b) Suggest any three ways to increase the friction and three ways to reduce the friction.
OR
a) Define Pressure. Write the relation between pressure, force and area.
b) Compare the pressure exerted by the box in two cases if a force of 15 N is applied on it.
4m
5m
3m
5m
3m
4m
SECTION B-BIOLOGY (33 Marks)
1. Choose the correct answer for the following:i. Which of the following provides a lot of humus to the soil?
a) Fertilizers
b) Seeds
c) Manures
Ii The soil which needs least frequent irrigation is :
a) Sandy
b) Clayey
c) Rocky
iii. The microbe which is helpful to decompose waste organic matter:
a) Bacteria
b) Fungi
c) Viruses
iv. Fermentation of sugar is done by____________:
a) Bacteria
b) Fungi
c) Yeast
v. ____________________ is an exotic species.
a) Bengal Tiger
b) Blue Whale
c) Asiatic Lion
vi. Arctic Tern migrate from Arctic region to
a) America
b) India
c) Europe
(1X6= 6 )
d) Pesticides
d) loamy
d) Algae
d) Algae
d) Eucalyptus
d) Antarctica
2. (a) The ______________ is an endemic aquatic animal that lives only in the river Ganga.
(b) In what forms do all living organism get N2.
(1)
(1)
3. (a) Excessive use of fertilizers is not good. Why?
(b) Write an example of:
(i) Manure
(ii) Fertilizers.
(2)
4. Give reasons, why?
(a) Drip system of irrigation is a water economical method.
(b) Animals migrate from one place to another place.
(c) Foods stores in refrigerators are preserved.
(2x3=6)
5. Write one advantage of: (i) Ploughing
6. Give an example of:
(a) Endangered species
(ii) Transplantation
(iii) Weeding
(3)
(3)
(b) Endemic species
(c) Extinct species-
7. How the curd is formed from milk? Explain with the help of a chemical reaction.
(3)
8. See the relationship and complete the following.
(a) Dengue fever
:
Virus
: :
Cholera
:
(b) Gir National Park :
Asiatic Lion : :
Kanha National Park :
(c) Seed-Drill
: Sowing
: :
Trowel
:
OR
Circle the odd one. Give reason for your choice.
(a) Moat, Dhekli, Sprinkler, Rahat
(b) Bread, Pastries, Curd, Idli
(c) Blue whale, King Cobra, Snow leopard, Pink headed Duck.
(3)
______________
______________
______________
9. (a) What do you mean by food poisoning?
(b) Name any one bacterium and fungi causing food poisoning.
(c) Describe any 3 Methods of food preservation with the principle on which they are based.
OR
Explain the following steps involved in Nitrogen cycle
(a) Nitrogen Fixation
(b) Nitrogen assimilation
(c) Ammonification
(d) Nitrification
(e) De-nitrification.
SECTION C-CHEMISTRY (28 Marks)
1. Tick the correct option:
i. The property of metals by which they can be beaten in to thin sheets is calleda) Malleability
b) Ductility
c) conduction
d) Expansion
ii. Which one of the following is metal
a) C
b) N
c) Na
d) O
(5)
(1x6)
iii. Which one of the following is non metal?
a) Zn
b) Al
c) Fe
d) N
iv. Which of the following is a natural resource?
a) Tea
b) Cooked Food
c) Air
d) Toffee.
v. Inexhaustible natural resources in nature are
a) limited
b) Unlimited
c) Scarce
d) Not present.
vi. Resources which are limited in nature are Known as
a) Exhaustible
b) Inexhaustible
c) unnatural
d) None of these
2. Name the metal used in thermometer.
3. Give the reactivity series of Cu, Zn and Fe.
4. Give Reasons, why?
(1)
(1)
(3x2=6)
(a) Phosphorus is stored under water.
(b) Handle of screw driver is not made up of metal
(c) Why is CNG being used as a fuel for vehicles?
5.
Why does a copper vessel acquire green coating if it is exposed to moisture for a long time? Write
the reaction also.
(3)
6.
What are the two kinds of natural resources? Explain giving examples.
(3)
7.
What is rusting of iron? Write the reaction also.
(3)
OR
What happens when the following metals react with Oxygen? (Write chemical equation only)
Sodium
(b) Zinc
(c) Magnesium
8.
Draw a well labeled diagram for the flame of a candle and answer the following questions:
(a) Which zone is luminous and why?
(b) Why is the innermost zone grey in colour and the coldest zone?
(c) Which zone is called the zone of complete combustion and why?
OR
Explain the process of refining of petroleum with the help of diagram.
(5)
DWARKA INTERNATIONAL SCHOOL
METALS AND NONMETALS
CLASS VIII CHEMISTRY
1 Match the following
a) Mercury
a) Bad conductor
b) Sulphur
b) Hydrogen gas
c) Gas that burns with ‘pop’ sound
c) Blood
d) Iron
d) Thermometer
2. Fill in the blanks
a) Acids turn ______ litmus to ______ litmus.
b) Bases turn ______ litmus to ______ litmus.
c) Metals form ______ oxides and non metals form ______ oxides.
d) Copper does not react with ______ acid even on heating but it reacts with sulphuric acid.
e) A material which conducts electricity is called______.
f) Reactions of non metals with bases are ______.
3 Tick the correct option
a) A liquid metal ______
i) Sulphur ii) Gold iii) Mercury
b) Metals, non metals and metalloids are ____
i) Compounds II) Elements III) Matter
c) Which is the best conductor of electricity.
i) Copper II) Silver III) Iron
d) Elements which are ductile and malleable are ______
i) Non- metals II) Metals III) Metalloids
4 Give one word/one sentence answer
a) Name a metal which can be cut with a knife.b) Name the metal used in thermometer.
c) Give the reactivity series of Cu, Zn and Fe.
d) Which gas is evolved when metals react with sodium hydroxide and water.
e) What is the colour of CuSO4 and ZnSO4 ?
f) Non-metals react with water or not.
g) Name the acid formed when sulphur dioxide is dissolved in water.
5 Write true or false
a) Generally non -metals do not react with water and acids.
b) Metals do not react with bases.
c) Silicon is an example of metalloid.
d)Element does not contain one kind of atom.
6 Give reasons
a) Phosphorus is stored under water.
b) Handle of screw driver is not made up of metal.
c) Metallic pan has wooden handle.
d) Bells are made up of metals and of wood.
e) Metals are drawn into wires and beaten into sheets.
7. a) Give differences between Metals and Non metals on the basis of their physical properties and chemical
properties.
b) Draw a diagram of ‘Electrical Tester’.
8 Answer the following questions
a) Give 3 examples of each i) Metals II) Non metals.
b) Why does a copper vessel acquire green coating if it is exposed to moisture for a long time. Write the reaction
also.c) What is rusting of iron? Write the reaction also.
d) Write 5 uses of metals.
e) Write 5 uses of non metals.
f) Write the reaction for displacement reaction and explain it.
9 Complete the reactions and write in words
a)2 Mg + O2 ---b) SO2 +H2O -----c) CuSO4 +Zn ------d) Fe + O2 + H2O ------e) 2Cu + H2O +CO2 + O2 -----f) FeSO4 + Cu ----g) CuSO4 + Fe -----h) ZnSO4 + Fe -------
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