sciences for class 8

7/31/2019 Sciences for Class 8

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Model Papers

PAPER 1

Subjective type Questions

1. Describe different methods of preservation of food.

2. Explain selective breeding.

3. What is a lens? Explain the different between convex and concavelens?

4. Describe the occurrence of minerals found in our country and theirusage.

Fill in the blanks.

1. Equator is hotter because sunlight strikes there_______.

2. Virus is a _______ word.

3. Algae contain_______.

4. Global warming is taking place due to _______effect.

5. _______ bear hereditary units or genes.

6. Sui gas is_______ gas.

7. Na Na++_______.

8. Acid present in vinegar is _______.

9. Coal is _______ form of Carbon.

10.There are _______ lenses in our eyes.

Choose the correct answer

1. Rice plants belong to the group of plants:a. Mosses b. Fernsc. Conifers d. Flowering plants

2. Name the animal with jointed legs:a. Jelly fish b. Butterflyc. Starfish d. Octopus

3. Which of the following is the hereditary material:a. DNA b. chloroformc. Interferon d. Insulin

4. When iron gets rust it reacts with:a. Air b. Oxygen in airc. Nitrogen in air d. Oxygen and water

5. Which is not a nitrogenous fertilizer:a. Uerab. Ammonium sulphatec. Ammonium phosphated. Calcium hydrogen phosphate.

6. The unit of pressure is.a. Kilo joule per moleb. Caloriec. Pascald. Ampere

7. The liquid usually filled in the bulb of mercury is _______.a. Water b. Alcoholc. Mercury d. Benzene

8. Pupil is made small or large by:a. Ciliary muscles b. Cornea


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Model Papers General Science 8th

c. Iris d. Retina

9. The voltage supplied to homes isa. 220 volts b. 100 voltsc. 440 volts d. 1000 volts

10. The study of fossils is called.a. Battery b. Zoologyc. embryology d. Paleontology

Mark the following statements true or false.

1. SARS is a viral disease.

2. Wood of conifers is used in making furniture.

3. Insulin is a gene.

4. Nitrate radical can be written as No31.

5. NaOH + HCl NaCl +H2+O2

6. Diamond is a good conductor of heat.

7. Urea is a nitrogenous fertilizer.

8. The size of 1K and 1o F are equal.

9. In Karachi KANUPP is producing electricity.10.Some minerals are made up of only one element.

Match the column (A) with column (B).

No. Column (A) Column (B) Column (C)

1.Formic Acid Orange

2. Acetic Acid Dehyderating agnet3. Oxalic Acid Apples4. Citric Acid Salt5. Tartaric Acid Ants

6. lactic Acid Tomatoes7. Malic Acid Grapes8. Sulphuric Acid Vinegar9. Sodium Carbonate Base10. Potassium Hydroxide Curd

Short Question.

1. Define species.

2. Write down two characteristic of ferns.

3. Define global warming.

4. What is the use of interferon?

5. Uses of sodium carbonate Na2Co3.

6. Define Pressure.

7. Why ice floats on the surface of water?

8. How white dwarf is converted to black dwarf?

Fill in the BlanksAnswers

1. Directly 2. Latin 3. Chlorophyll 4. Green house

5. Chromosomes 6. Methane 7. (e) 8. Acetic Acid9. Amorphus 10.Two


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Model Papers

Correct Answer

Answers

1. d 2. b 3. a 4. d5. d 6. c 7. a 8. c9. a 10.d

True /False

Answers

1. T 2. T 3. F 4. T5. F 6. F 7. T 8. F9. T 10. T

Match the Columns1. Ants 2. Vinegar 3. Tomatoes 4. Orange5. Grapes 6. Curd 7. Apples 8. Dehydrating agent9. Salt 10.Base

Short Question1. A group of closely resembling organisms that breed with one another in nature is calledspecies.2. i. They have well developed roots, stens and leaves.

ii. They do not produce flowers, fruits and seeds.3. The increase in temperature of the earth due to green house effect is called globalwarming.4. Interferon is a substance that protects body against Cancer.5. Sodium carbonate is used for

i. Softening of hard water.ii. The manufacture of glass and soap.

6. The perpendicular for force acting on a unit area of a surface is called pressure.

7. The density of ice is less than the density of water, therefore it floats on the surface ofwater.8. During the process of cooking down of white dwarf, initially it is converted into red

dwarf and then into black dwarf at the complete emission of light.


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PAPER 2


1. Why classification of living organisms is necessary?

2. Give three uses of

a. Graphite b. Diamond

3. Explain expansion of liquids with the help of an experiment.Moreover, write one use of thermal expansion.

4. How sedimentary and metamorphic rocks are formed? Explain it.

Fill in the blanks.

1. Pair of tongs is a lever of _______.

2. Iron sulphide is the chemical name of _______.

3. _______ are present in fish for breathing.

4. Calcium phosphate is _______in water.8. Diamond an allotrope of carbon, is a bad conductor of _______ and _______ .

9. Structurally fungi are composed of numerous thread like structures called._______.

10.Molecular formula is written only for those compounds which exist as_______.

11.All alkalies are bases but all bases are not, _______.

9. Ozone depletion may cause _______ and _______.

10.Felling of trees and destruction of forests is called._______.


1. If we draw a horizontal line in a liquid the pressure would be:

a. Different at different parts of the line.a. Same on all of its parts.a. Larger on its right side than on its left side.a. Maximum at the center of the line.

2. The element needed for the growth of plant alongwith nitrogen andpotassium:

a. Sodium b. Phosphorusc. Sulphur d. Chlorine

3. Which acid is found in Tomatoes?a. Citric acid b. Tartaric acidc. Oxalic acid d. Formic acid

4. Carbon exists in two crystalline forms as diamond and graphite. These arecalled:

a. Isotopes b. Allotropesc. Isomers d. None of these

5. The king of chemicals is:a. KOH b. HCle. H2SO4 d. NaCl

6. Tell the total number of atoms in Fe2(SO4 )3:a. 6 b. 17e. 13 d. 7

7. What are the differences in the characteristics of members of a speciescalled?

a. heredity b. hereditary charactersc. variations d. genes


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Model Papers

8. What will be now the arrangement of electrons when potassium and brominereact?

a. Electron is transferred from potassium to bromine.b. Electron is transferred from bromine to potassium.c. There is a mutual sharing of electrons between bromine and potassium.d. There is no change in arrangement of electrons.

9. Which chemical causes Ozone depletion?a. Hydrogen

b. Chlorofluorocarbonsc Ultra-violet radiationd. Oxygen

10. The group of plants which includes hetrotrophs:a. Algae b. Fungic. Mosses d. Ferns

Mark the following statements true or false.

1. Natural materials found on the earth are called minerals.

2. An ionic bond is formed by the mutual sharing of electrons between atoms.

3. Pure diamonds are colourless.

4. Carbon dioxide is a supporter of combustion.

5. Potassium is extracted from potassium sulphate.

6. The ray parallel to the principal axis after refraction from convex lens passesthrough the center of curvature.

7. Chromosomes are present in the cytoplasm of the cell.

8. Butterfly is an insect.

9. When substances burn, carbon dioxide and water are formed.

10.Clay is transformed into marble due to extreme pressure.


No. Column (A) Column (B) Column (C)1. Ore of iron Uranium2. Ore of chromium Halite3. Nuclear fuel Metamorphic rock4. Preparations of

Sulphric acidHemolite

5. Preparations of Phosph-rus

Copper

6. Calcium sulphate Chromite7. Sodium chloride Gypsum8. German silver Sulpher

9. Graphite Igneous rock10. Rhyolite Phosphate rock

Short Question.

1. What is meant by rocks?

2. Upon what factor does the amount of light entering in a cameradepend?

3. Mention the uses of two salts in industries.

4. What is catenation?

5. Why silver jewellery tarnish with lime?

6. Which crystalline form of carbon is a good conductor of electricity?

7. Write two characteristics of flatworms.


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8. Why is hydal power preferable to thermal power?

Fill in the Blanks

Answers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. Third kind 2. rust 3. gills 4. insoluble5. heat, electricity 6. hyphae 7. molecule 8. alkalies

9. eye disease,cancer

10.

deforesting

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. b 2. b 3. c 4. b5. c 6. b 7. c 8. a9. b 10. b

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. T 2. F 3. T 4. F5. T 6. F 7. F 8. T9. F 10. F

Match the ColumnsNo. Ans1. Hemolite2. Chromite

3. Uranium4. Sulpher5. Phosphate rock6. Gypsum7. Halite8. Copper9. Metamorphic

rock10 Igneous rock

Short Question1. The solid materials making the crust of the earth are called rocks.

2. The amount of light entering into camera depends upon the size of aperture. In factaperture is an opening in the diaphragm. This can be made small or larger according toour need.

3. i. Uses of Sodium chloride NaCl; Sodium chloride is used in the manufacture ofa. Chlorine gas Cl2b. Caustic soda NaOHc. Hydrochloric acid HCld. Washing soda Na2CO3 10H2Oii. Uses of Sodium carbonate Na2CO3; Sodium carbonate is used fora. Softening of hard waterb. The manufacture of glass and soap.

4. The ability of carbon atom to link with other carbon atoms to form long chains or rings

is called catenation.5. It is due to chemical reaction between silver and lime.6. Graphite is a good conductor of electricity.7. i. Their body is flat, broad and ribbon like.

ii. They are attached to the host by suckers.


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Model Papers

8. Hydal power is preferable to thermal power because it is of low cost and produces nopollution.

PAPER 3


1. Write a short essay on the use of knowledge of inheritance inhuman welfare.

2. Write down the names of ten things used at homes which arecomposed of carbon compounds.

3. Describe viruses are living or non-living.

4. Which laws are obeyed when a chemical reaction takes place?Explain these laws with the help of examples

Fill in the blanks.

4. The _______ gametes of a flower are called Anther.

5. 2H2+O2_______.

3. Plants in which seeds are not present in the fruit are called_______.

4. Wings help birds in _______.

5. One carrot is equal to _______ mg.

6. An Aluminium ion carries _______ charges.

7. The sun is at the_______ distance from the center of the Milky Way galaxy.

8. All species living in an area form a _______.

9. Liquid pressure acts _______ on the surface of the containing vessel.

10.The _______ used for nuclear power is uranium or plutonium


1. The activity of metallic ball and ring shows:a. Solid objects expand on heatingb. Solids contract on heatingc. Solids change their nature on heatingd. There is no effect of heat on solids

2. The raw material, other than air, needed to produce urea fertilizer isobtained from:

a. Natural gas

b. Chlorine gasc. Sulphur dioxide gasd. None of these

3. The unit of electric power is:a. Ampere b. Voltc. Watt d. Kilowatt-hour

4. The pressure at any point in a liquid depends upon:a. Depth of the pointb. Area of the mouth of the vessel.c. Area of the bottom of the vesseld. The thickness of the containing vessel.

5. Rice plant belongs to the group of plants:a. Mosses b. Fernsc. Conifers d. Flowering plant


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6. Ionic formula tells the:a. Actual ratio which exists between all atoms.b. Total number of atomsc. Simplest ratio present between different atoms.d. All the above statements are true.

7. What ratio is present between masses of hydrogen and oxygen in hydrogenperoxide (H2O2)?a. 1:16 b. 16:1

c. 1: 8 d. 8:18. In a candle flame partial combustion takes place in:

a. The dark zone around the wickb. The yellow zonec. Small blue zone below the flame

9. For the production of detergents, raw material is obtained from:a. Rocks b. Airc Naphtha d. Natural gas

10. Which fertilizer is used to compensate for the deficiency of phosphorus inplants

a. Super phosphateb. Phosphoric acidc. Sodium phosphated. Calcium phosphate

Put ( ) mark against correct statement and ( ) for Incorrectstatement.

1. The planets revolving between Mars and Jupiter are called meteoroids.

2. Water is filled in the bulb of thermometers.

3. Liquid exerts pressure on the surface of the containing vessel in all direction.

4. Bacteria are of three types according to shape and form.

5. Sand and mud are also rocks.6. Chlamydomonas is an example of unicellular algae.

7. Acids turn red litmus blue.

8. Animal charcoal do not absorb colour

9. Burning adds pollutions to the atmosphere.

10.No atom can exist independently.


No. Column (A) Column (B) Column (C)1. Electrical Energy 1.5 volts

2. Power 220 volts3. Potential difference Nuclear power

station4. Dry cell Hydal power station5. Car battery Kilowatt hour6. Electricity supply to

our homesWindmill energy

7. Mangla Dam Volt8. Kanupp Watt9. Multan Thermal power plant10. USA 12 volts

Give Short answers.

1. Name two diseases which have been understood and are beingtreated by using knowledge of inheritance.


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Model Papers

2. What is the use of a bi-metallic plate?

3. The lighting of bulb is a physical change. Why is it not a chemicalchange?

4. What is a difference between Sterilization and Pasteurization?

5. Complete the following.

i. Mg+2HCl

ii. Mg+2CH3COOH

6. Define focal length.

7. Can image be obtained on the screen by a concave lens?

8. Define classification and species.

Fill in the Blanks

Answers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. male 2. (2H2O) 3. conifers 4. flying5. (200) 6. (+3) 7. three hundred light

years8. community

9. normal 10. fuel

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. a 2. a 3. c 4. a5. d 6. d 7. a 8. b9. c 10. a

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. T 2. F 3. F 4. F5. T 6. T 7. F 8. F9. T 10. T

Match the ColumnsNo. Ans1. Kilo watt hour2. Watt3. Volt4. 1.5 volts5. 12 volts6. 220 volts7. Hydal power station8. Nuclear power

station9. Thermal power plant10 Windmill energy


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Short Question1. i. Hemophilia

ii. Thalassemia2. When a bi-metallic plate is heated or cooled, it bends. The curvature thus produced is

used to control the temperature of oven, electric iron and refrigerators.3. Lighting of bulb is a physical change because in this process no new thing is produced.

The wires of the bulb come to original state when the current is switched off.4. In Pasteurization, food is preserved by exposing it to a high temperature of 120oC to

126oC, under pressure for 12 to 90 minutes.

5. i. Mg+2HCl MgCl2+H2ii. Mg+2CH3COOH (CH3COO)2 Mg+H2

6. The distance between the optical centre and principal focus is known as focal length ofthe lens.7. No a virtual image is formed by a concave lens. This image is erect and smaller in size.

8. ClassificationThe grouping of living organisms on the basis of similarities and differences is called

classification.A group of closely resembling organisms that breed with one another in nature is called

species.


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Model Papers

PAPER 4


1. Classify flowering plants. Describe salient features of each groupand give examples.

2. What is meant by biotechnology? Explain briefly tissue culture and

genetic engineering.

3. Describe salient features of animals with jointed leg and giveexamples.

4. How are hereditary characters passed on to the next generation?

Fill in the blanks.

1. Algae contain_______

2. Beneficial variations help organism to _______ the environment.

3. Raw material for the preparation of detergents is obtained from_______.

4. Births per thousand in an area are called _______.

5. Cholera and T.B. in man are caused by _______.

6. In writing the formula of an ionic compound the negative radical is written on_______ and the positive radical is written on _______.

7. The simplest form of matter which cannot be further sub divided is called_______.

8. Raw material obtained from _______ is used to produce phosphate fertilizers.

9. Bases have _______ taste.

10.An animal or plant resulting from the cross between two different varieties is called_______.


1. The image formed by a concave lens is:a. Virtual b. Realc. Inverted d. Larger

2. A dry cell provides a voltage of :a. 1 volt b. 1.5 voltsc. 2 volts d. 3 volts

3. Pupil is made small or larger by:a. Cilliary muscleb. cornea

c. Iris d. Retina4. Bacteria which produce diseases in plants and animals are called:

a. Heterotrophic bacteriab. Autotrophic bacteriac. Parasitici bacteriad. Pathogenic bacteria

5. Name the animal which has jointed legs?a. Jelly fish b. Butterflyc. Octopus d. Starfish

6. Ozone layer stops _______ radiations from coming to earth:a. Light b. Heat

c. Infra-red d. Ultra-violet

7. The number of elements found naturally, are:a. 90 b. 88c. 98 d. 109


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8. When iron gets rust, it reacts with:a. Air b. Oxygen in airc. Nitrogen in air d. Oxygen and water in air

9. Apart from potassium chloride, which compound is used as a source ofpotassium:

a. Potassium hydroxideb. Potassium carbonatec Potassium nitrate

d. Potassium dichromate10. What indications you commonly observe when a chemical reaction takesplace?

a. Liberation of heat, light or a gasb. Liberation of heat and lightc. Liberation of light or gasd. Liberation of heat or gas


1. The pressure at any point in a liquid depends upon the extension of the mouth of

the containing vessel.2. Sodium hydroxide does not change the colour of phenolphthalein.

3. All carbonates react with mineral acids liberating CO2 gas.

4. Bacterium has nucleus like typical plant and animals cell.

5. Sodium chloride (Table salt) is an ionic compound.

6. Rochelles salt is used as a laxative.

7. CO2 is basic in nature.

8. Pascal is the unit of work.

10.The density of water is maximum at 0oC.

11.Wind mills are very noisy.


No. Column (A) Column (B) Column (C)1. Photosynthesis Physical change2. Burning of candle Potash alum3. Water change of

steam iceCombination

4. Fe+S FeS Plants prepare theirfood

5. CaCO3 CaO+CO2

Aqua Regia

6. Acid + Base Simple decomposing7. 3Hcl+HNO3 Chemical change8. Dyeing cloth Potassium nitrate9. Fungicide Neutralization10. Gun powder Copper sulphate

Give Short answers.

1. Define genetic engineering and biotechnology.

2. Why one end of iron girders is placed on rollers in construction of

bridges and in roof structure of buildings?

3. Define a lens?


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Model Papers

4. Define classification.

5. What is meant by fossils?

6. Why do you feel cool when you sit under a ceiling fan after taking a bath?

7. Why two section of railway track are joined together by fish plates?

8. Write five names of sedimentary rocks.

Fill in the Blanks

Answers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. Chlorophyll

2. Adapt 3. Naphtha 4. Birth rate

5. Bacteria 6. Positive radical, negativeradical

7. element 8. Phosphaterocks

9. Bitter 10. Hybrid

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. a 2. b 3. c 4. c5. b 6. d 7. d 8. d9. c 10. a

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. F 2. F 3. T 4. F5. T 6. T 7. F 8. F9. F 10. T

Match the ColumnsNo. Ans1. Plants prepare their

food2. Chemical change3. Physical change4. Combination5. Simple

decomposition

6. Neutrilzation7. Neutr Aqua Regia8. Potash alum9. Copper sulphate10 Potassium nitrate

Short Question1. Genetic engineering

It is a biotechnology in which selected genes from an organism are inserted into DNA ofthe bacteria and the bacteria then start producing materials according to theintroduced genes.

BiotechnologyThe industrial use of organisms specially the micro-organisms such as bacteria forhuman welfare is called biotechnology

2. Iron girders are used in the construction of bridges and roof of big buildings. One end ofthese girders is placed on rollers so that it can move forward or backward according torise or fall of temperature.


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3. It is a piece of transparent material which is bonded by two spherical surfaces.4. The grouping of living organisms on the basis of similarities or differences is called

classification.5. Fossils are the remains or signs of dead animals or plants of ancient times present insome rocks.6. Heat is required for the water attached to the body. This heat is taken from the body

when we sit under the fan. That is why we feel cool.7. The two sections of a railway track are joined together by fish plates. The fish plates

are softened by nuts and bolts which are able to slide along the oval holes of the plate.When the rails expand or contract due to rise or fall of temperature , they slide alongthe fish plates and hence prevent the buckling of the tracks.

8. i. Basaltii. Graniteiii. Gabbroiv. Rhyolitev. Pegmatite


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Model Papers

PAPER 5



2. Explain selective breeding.

3. What are the sources of carbon dioxide in nature?

4. Describe the occurrence of minerals found in our country and their usage.

Fill in the blanks.

1. Meat mincing machine is an example of _______.

2. An ionic bond involves the transference of _______ between atoms.

3. Rainbow is formed due to dispersion of _______.

4. Caustic soda and _______ are heating together to get soap.

5. Graphite is _______ in colour.

6. Real _______ can be obtained on the screen.

7. _______ is the chemical name of lime stone.

8. Plants without vascular tissues are called _______ plants.

9. Tartaric acid is present in _______.

10.Liquid exerts pressure at a point inside the liquid _______.


1. The group of animals belongs to warm blooded animals:a. Fish and birdsb. Fish and mammals

c. Fish and reptilesd. Birds and Mammals

2. Which statement is not true for tissue culture?a. It is a type of vegetative propagationb. New plants are different from parental plants.c. Disease resistant plants are produced by this technology.d. It is an asexual reproductive process like stem cutting.

3. Malic acid is found in:a. Grapes b. Tomatoesc. Ants d. Apples

4. What is the effect of dilute HCl on the colour methyl orange:a. red b. pinkc. blue d. orange

5. In free state carbon occurs as:a. CO2 b. Coal gasc. Marble d. Diamond

6. Which is not a nitrogenous fertilizer:a. Ammonium sulphateb. Calcium hydrogen phosphatec. Ammonium phosphated. Urea

7. In state of rest, the level of free surface of a liquid is:a. Higher at some places and lower at othersb. Higher at the edge of the vessel.c. Same every whered. Lower at the edge of the vessel


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8. The value of 60oC on Fahrenheit scale would be:a. 65oC b. 51oCc. 76oC d. 140oC

9. Fossils are mostly found in rocks:a. Igneous rocksb. Sedimentary rocksc Metamorphic rocks

10. Thermal expansion does not take place in the:a. An automatic fire alarmb. Thermostatc. Fixing of iron rings on wheelsd. Swing of a pendulum


1. The pressure at any point inside the liquid is lesser in the upward direction than thepressure in the downward direction.

2. Compounds are always made up of ions.

3. The formula of sodium carbonate is NaCO3.

4. Acetic acid is found in grapes.

5. In luminous zone of candle flame complete combustion takes place.6. The image of an object placed at the principal focus of a convex lens is formed at

infinity.

7. The image formed by convex lens is always erect.

8. There are hundred billion stars in the Milky Way galaxy.

9. Starfish is a kind of fish.

10.A battery provides potential difference across a conductor.


No. Column (A) Column (B) Column (C)1. Paramecium Coral reefs2. Spongilla flatworms3. Jelly fish Reptiles4. Leech Shelled animals5. Tapeworm Spiny animal6. Butterfly Unicellular Animal7. Snails Segmented worms8. Starfish Amphibian9. Toad Sponges10. Tortoise Jointed leg animal


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Model Papers

Give Short answers.

1. Define electric power.

2. The boiling point of water is denoted by _______ in Fahrenheit scale.

3. When a vessel full of a liquid is heated, the level of liquid initially falls andthen it rises why it happens so?

4. What is the structure of a concave lens?

5. What forces of attraction are present between Na and Cl in sodiumchloride?

6. Define pressure.

7. What is meant by migration?

8. What are the differences between mosses and ferns?

Fill in the Blanks

Answers

No

.

Ans. No

.

Ans. No

.

Ans. No

.

Ans.

1. Wheel andAxle

2. Electrons 3. Light 4. Vegetable oil/Animalfats

5. Grey 6. Image 7. Calciumcarbonate

8. Mosses

9. Grapes 10. Equally

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. d 2. a 3. d 4. a

5. d 6. b 7. c 8. d9. b 10. b

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. T 2. T 3. F 4. F5. T 6. T 7. T 8. T9. F 10. T

Match the ColumnsNo. Ans1. Unicellular animal2. Sponges3. Coral reef 4. Segmented worms5. Flatworms6. Jointed leg animals7. Shelled animals8. Spiny animals9. Amphibian10 Reptiles

Short Question1. The electrical energy consumed or converted into other forms of energy in one second

is called electrical power.2. 212oF


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3. The level of liquid on heating in a vessel initially falls because the vessel expands first.Then the liquid start expanding.

4. Concave lens is thin at the middle and thicker at the edges.5. The electrostatic force of attraction the oppositely charged ions (Positively charged

Na+ion and negatively charged clion) to form NaCl and these forces are present in ionic

bond of NaCl.6. Pressure is the force per unit area acting perpendicular on a surface.7. If some individuals move out of an area (from villages to cities) due greater job

opportunities, better health and education facilities is called Migration. Results in theincrease of population of cities in this case.

8. i. Mosses lack true roots, stems and leaves, but roots stem and leaf like structures arepresent. Ferns have well developed roots, stems and leaves.

ii. Vascular tissues are absent in mosses whereas, fern have well developed vasculartissues i.e, xylem and phloem.

iii. Examples of mosses are Funeria and Polytrichum. Examples of Ferns are Dryopteris,Pteris and Adiantum.


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Model Papers

PAPER 6


1. Define and explain potential difference.

2. Discuss four different zones of a candle flame.

3. Identify the group of following plants with the help of plant key:

Chlamydomonas, Mushroom, Funaria, Adiantum, Pinus, Maize,Sarson.

4. Micro-organism is a diverse group of living organisms. Explain.

Fill in the blanks.

1. Wheel borrow is a _______ of second kind.

2. Oxidation is a _______ property.

3. Bacteria are _______ micro-organisms.4. Mostly fossils are found in _______ rocks.

5. Acids react with bases to form water and _______.

6. Diamond and_______ are the _______ forms of carbon.

7. The simplest ration present between the masses of carbon and oxygen in carbondioxide is _______.

8. Lime stone, clay and_______ are used as raw materials for the production of cement.

9. The lightest among the elements is_______.

10._______ is used as a source of potassium.

Choose the correct answer1. The change in direction of light passing from one medium to another is

called:a. reflection b. refractionc. dispersion d. irregular reflection

2. The types of rocks basically are:a. one b. twoc. three d. four

3. If we consider a point inside the liquid:a. The upward pressure on this point would be larger than the downward pressureb. Pressure at this point from the right direction would be least.

c. Pressure on its right side would be greater than the pressure on its left side.d. Pressure on it would be the same from all directions.

4. The compound used to produce glass:a. Caustic soda b. Washing sodac. Baking soda d. PVC

5. Carbogen is a mixture of oxygen and carbon dioxide. Percentage of carbondioxide in this mixture is:a. 30% b. 50%c. 70% d. 20%

6. The group of animals belongs to cold blooded animals:

a. Fish, amphibians,b. Fish amphibians, mammalsc. Fish, amphibians, reptilesd. Fish, reptiles, birds


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7. Sedimentary rocks has the example of:a. Basalt b. Marblec. Gypsum d. Clay

8. The point through which ray of light passes without changing its path is the:a. centre of curvatureb. principal axisc. optical centred. principal focus

9. Hydal power plant converts:a. mechanical energy into electrical energyb. electrical energy into mechanical energyc. chemical energy into electrical energyd. heat energy into electrical energy

10. The distance between the marks of 0oand 100oon the scale of Celsiusthermometer is 12cm. If the level of mercury thread is at 4.8 cm what wouldbe the temperature in Celsius scale?a. 72oC b. 40oCc. 104oC d. 25oC


1. A current is induced in the coil when a magnet is pushed into it.

2. Lamp black is used in printing ink.

3. The melting point of ice is denoted by 0oF in Fahrenheit scale.

4. Amphibians have hard and dry scales on their bodies.5. Group of atoms which keeps its identity during chemical reaction is called radical.6. Genes are made up of DNA.7. The size of 1oC is smaller than the size of 1oF.8. Rocks formed by the cooling of magma or lava are called metamorphic rocks.9. The temperature of red star is more than the temperature of blue star.

10.Iris is similar to aperture of the camera.


No. Column (A) Column (B) Column (C)1. Measles mosses2. Cholera Citrus fruit3. Canker disease conifers4. Fire blight Fungi5. Mushrooms Dicots6. Polytrichum Virus

7. Pteris Peach8. Pines monocots9. One cotyledon Bacteria10. Two cotyledons Ferns


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Model Papers

Give Short answers.

1. What is a ray diagram?

2. How is the focal length affected when the lens of eye becomes thicker?

3. Why water is not used in place of mercury in thermometers?

4. Give two differences between Dicots and Monocots.

5. Give examples of plants and animals being produced by hybridization andselective breeding.

6. Why is manganese dioxide and carbon powder used in the dry cell?

7. What is difference between cold blooded and warm blooded animals?

8. Name a salt which can reduce the acidity in our stomach.

Fill in the Blanks

Answers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. lever 2. Physical 3. Unicellular 4. Sendimentary5. Salts 6. Graphite,

Allotropic7. 3:8 8. Calcium

9. Hydrogen 10. Potassiumchlorate

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. b 2. c 3. d 4. b

5. b 6. c 7. c 8. c9. a 10. b

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. T 2. T 3. F 4. F5. T 6. T 7. F 8. F9. F 10. T

Match the ColumnsNo. Ans1. Virus2. Bacteria3. Citrus fruit4. Peach5. Fungi6. Mosses7. Ferns8. Conifers9. Monocots10 Dicots

Short Question1.

The method to trace image geometrically is called ray diagram.


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2. When we look at something close to us the muscles make the lens thicker. This makesits focal length shorter and the image is formed again on the retina and is not formedagain at a point beyond it. Hence the focal length is effected when the lens of the eyebecomes thicker.

3. Water freezes to ice at 0oC and boils at 100oC. Mercury does not frazeat at oC and doesnot boil at 100oC. Moreover mercury has a silvery shine which makes a better visiblematerial than water.

4. i. Dicots have two cotyledons and monocots have one cotyledons.ii. Dicot have broad lens and monocots have long and needle like leaves.

5. Examples of plants produced through hybridization and selective breeding.i. Maxi pak wheatii. Super Kernal basmati riceiii. Kinnowiv. GuavaExamples of animals produced through hybridization and selective breeding.i. Neoli Ravi buffaloii. Sahiwal cowiii. Teddy goat (short satu red goat)

6. Because the mixture of mangnese dioxide and carbon electrode retain moisture in it. Ithelps the cell to work for a long time.

7. Cold blooded animals cannot keep their body temperature constant. Their bodytemperature changes with that of environment (water) e.g; Fish, crocodile etc. Warmblooded animals can maintain constant body temperature. Their body temperaturedoes not change with the change in environment e.g, Mammals.

8. Sodium bicarbonate NaHCO3


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Model Papers

PAPER 7


1. Describe salient features of fish and give examples.

2. What is a base? Write down the names and formulae of four bases?

3. Write down the advantages of bacteria.

4. Write a note on ozone depletion.

Fill in the blanks.

1. Car jack is an example of _______ .

2. The steam is a source of _______ energy.

3. Pigments are _______ colours.

4. The gigantic clouds of dust and gases in space are called_______.

5. Vinegar contains _______ acid.

6. Liquid pressure increases with its_______.

7. Mushroom is an example of_______.

8. The natural materials found on the Earth are called _______.

9. Naphtha is constituent of _______.

10.To increase the yield of agricultural products the growers commonly use _______fertilizers.


1. Which gas present in the atmosphere stops ultra-violet radiations from

reaching the earth?a. Oxygen b. Nitrogenc. Ozone d. Carbon dioxide

2. The process by which foreign DNA is incorporated in the DNA of the recipientis called:

a. Genetic engineeringb. Tissue culturec. Selective breedingd. Hybridization

3. The compound used alongwith vegetable oil for the preparation of soap:a. Sodium hydrogen carbonate

b. Sodium Sulphatec. Sodium hydroxided. Super phosphate

4. When carbon dioxide is passed through lime water, the milkyness is due tothe compound:

a. Ca(HCO3)2 b. CaCO3c. H2CO3 d. None of these

5. Our solar system is a part of galaxy:a. Ursa Major b. Andromedac. Milky Way d. Orion

6. The disease caused by bacteria is:a. Measles b. Small poxc. Cholera d. AIDS


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7. The property of expansion and contraction of liquids due to changes oftemperature is used in the instrument:a. Barometer b. Thermometerc. Manometer d. Bicycle pump

8. A lighted bulb consumes:a. Electrons b. Positive chargec. Electrolyte d. Electrical energy

9. A thing telling about the age of Earth, its history and evolution of life presenton it:

a. Rocks b. Mineralsc. Fossils d. Metals

10. Neutron stars soutain_______.a. Neutron b. Protonc. Electron d. Positron


1. The lens in the eye moves back and forth to focus the image on retina.

2. Several thousand years are spent in the formation of sedimentary rocks.3. The cluster of stars is called constellation.

4. Heat is produced by the process of nuclear fission in a thermal power plant.

5. Tissue culture is a type of sexual reproduction.

6. Calcium carbonate is used as raw material for the manufacture of cement.

7. Plants need phosphorus and calcium for their growth in addition to nitrogen.

8. Chlorine gas is a molecular compound.

9. Element are usually found in solid state.

10.The sizes of 1 K and 1oF are equal.

Match the column (A) with column (B).No. Column (A) Column (B) Column (C)1. Ammonia AlCl32. Methane (NH4)2 CO33. Calcium chloride CO24. Aluminium chloride CaCl25. Aluminum phosphate K2SO46. Potassium sulphate NaCl7. Ammonium

carbonateH2O

8. Sodium chloride NH3

9. Carbon dioxide Al PO410. Water CH4


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Model Papers

Give Short answers.

1. Write down two characteristics of mammals.

2. Write down names of four diseases of man caused by virus.

3. Carbon dioxide gas is present in air. Can you guess how it is formed?

4. Write down two characteristics of ferns.

5. How is flour fermented?6. Why is rusting of iron faster in rainy season?

7. Why wind farm is made instead of one windmill for the production ofelectricity?

8. Define electro magnetic induction.

Fill in the Blanks

Answers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. Screw 2. Mechanical 3. Chemical 4. Nebula

5. Weak 6. Depth 7. Fungi 8. Minerals9. Crude oil 10. Phosphorous

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. c 2. a 3. c 4. a5. c 6. c 7. b 8. d9. c 10. a

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. F 2. F 3. T 4. T5. F 6. T 7. T 8. T9. T 10. F

Match the ColumnsNo. Ans

1. NH3

2. CH43. CaCl24. AlCl35. AlPO46. K2SO47. (NH4)2 CO38. NaCl9. CO210 H2O

Short Question

1. a. Mammals possess hair on their bodies.b. The female mammals feed their young ones on their milk.2. Following diseases of man are caused by viruses.

i. Measles ii. Small poxiii. Cancer iv. SARS


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3. Carbon dioxide is formed in air as a result ofa. Oxidation of organic matter i.e.,i. Wood ii. Petrolb. Burning of carbon i.e.,i. Charcoal ii. Sootiii. Coke iv. Coalc. Respiration of animals and plantsd. Volcanic activities

4. a. They have well developed roots, stems and leaves.b. They do not produce flowers, fruits and seeds.

5. When yeast is added to flour, the enzymes present in yeast bring about fermented offlour.

6. For rusting water and oxygen is needed. This is too much during rainy season than thedry season.

7. For large scale power generation, a wind farm with a hundred or more wind mills isneeded because one wind mill for the production of electricity is not suitable andeconomical.

8. The generation of current due to relative motion between magnet and coil is calledelectromagnetic induction.

PAPER 8



2. Write a note on green house effect and global warming.

3. What is electromagnetic induction? Explain it.

4. What is the difference between an ionic bond and a covalent bond?

Fill in the blanks.

1. Rolling friction is always more than _______ friction.

2. Nichrome is an alloy of Nickel and _______.

3. Elements usually exist in the form of _______.

4. Animals consisting of _______ are called vertebrates.

5. The commonly used nitrogen fertilizer in the world is _______.

6. Living organisms are arranged into different groups on the basis of similarities anddifferences. This grouping is called._______.

7. Plants which prepare their own food through process of photosynthesis are called

_______.8. The shining objects of gases in nebula are called_______.

9. The melting point of ice is denoted by_______ in Kelvin scale.

10.10.The image formed by a _______ lens is always virtual.


1. The value of 113oF on Celsius scale would be:a. 63oC b. 45oCc. 77oC d. 81oC

2. Igneous rock has the example of:

a. Rhyolite b. Lignitec. Graphite d. Quartzite

3. In Pasteurization, milk is heated at:a. 62oC for half an hourb. 62oC for 15 seconds


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Model Papers

c. 71oC for half an hourd. 100oC for one minute

4. Which one of the following is a good absorber of gases:a. Coke b. Coalc. Potassium d. Sodium

5. Raw material used for the production of cement alongwith lime stone andclay:

a. Calcium b. Gypsumc. Potassium d. Sodium

6. Following animal is parasite:a. Amoeba b. Tapewormc. Mosquito d. Snail

7. If valency of oxygen is 2 and that of aluminium is 3 then the formula ofaluminium oxide will be:

a. AlO b. Al3O2c. AlO2 d. Al2O3

8. Human growth hormone and interferon are prepared these days by:a. tissue culture

b. hybridizationc. selective breedingd. genetic engineering

9. What is the action of caustic soda on the colour of red litmus:a. Turn blue b. Changes pinkc. Turns yellow d. None of these

10. Tell the name of disease caused by virus in the following:a. T.B b. Dysentryc. Typhoid d. Polio

Put ( ) mark against correct statement and ( ) for Incorrect

statement.1. When an atom accepts an electron, positive ion is formed.

2. The level of the free surface of a liquid is the same at its different parts.

3. Conifers are also called as Evergreen plants.

4. Power is measured in Kilowatt-hour.

5. The universe is contracting with the passage of time.

6. Coke is used for the extraction of iron in a blast furnace.

7. Vascular tissues are present in ferns.

8. The method of writing the formula of a molecular compound an ionic compound issame.

9. All viruses are parasites.10.A concave lens spreads the rays out, therefore it is called a converging lens.


No. Column (A) Column (B) Column (C)1. Calcium CO2. Carbon Ag3. Chlorine Sn4. Cobalt Ca5. Copper S

6. Sodium Cu7. Silver Au8. Sulpher C9. Stamnum Na10. Gold Cl


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Model Papers

Give Short answers.

1. How carbon dioxide gas is obtained from molasses?

2. How does human body fulfill its energy requirements?

3. Name any two products which are being made through genetic

engineering.

4. Write name of two parasites which are found in man.

5. What is difference between Sterilization and Pasteurization?

6. Write four uses of carbon.

7. Define forestation.

8. How is lamp black prepared?

Fill in the BlanksAnswers

No.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. Sliding 2. Chromium 3. molecules

4. Vertebralcolumn

5. Urea 6. Classification

7. Autotrophs

8. Stars

9. 273 10. Concave

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. b 2. a 3. d 4. c5. b 6. b 7. d 8. d9. a 10. d

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. F 2. T 3. T 4. F

5. F 6. T 7. T 8. F9. T 10. F

Match the ColumnsNo. Ans1. Ca2. C3. Cl4. Co5. Cu6. Na7. Ag8. S9. Sn10 Au


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Short Questions1. It is obtained by the fermentation of molasses for the industrial preparation of ethanol,C2H5OH

YeastC H O 2C H OH+2CO12 2 5 2Fermentation6 6

2. During process of respiration , the digested food is oxidized and energy is released. Theenergy released by the oxidization of food fulfills the energy requirement of the body.

3. i. Insulinii. Interferon

4. i. Tapewormii. Threadworms

5. In sterilization, food is preserved by exposing it to a high temperature of 120oC to 126o,under pressure for 12 to 90 minutes.In pasteurization, milk is preserved by heating it at 71o C for 15 seconds or at 62oC for32 seconds.

6. i. Extinguishing fire.ii. Making sodium carbonateiii. The manufacture of ureaiv. Making carbonated beverages

7. Planting of trees and vacant hand is called forestation.8. Lamp black is prepared by burning kerosene or vegetable oil in the limited supply of

air. The root thus produced is deposited on a cool surface. This root is known as lampblack.


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Model Papers

PAPER 9


1. Mention the sources of the followings.

i. Citric acid ii. Tartaric acid iii. Acetic acid

2. Identify group of animals with the help of Invertebrate key.

Sea-anemone, Tape-worm, Ascaris, Earth worm, Cockroach, Snail,Starfish.

3. What is meant by thermal expansion? Explain expansion of solids withthe help of an experiment.

4. Explain how we come to know about life and environment conditionsexisting on earth in the past?

Fill in the blanks.

1. Root hair absorb salts, _______ and _______.

2. The meat contains _______ of water.

3. Common salt is used as a raw material is prepare _______.

4. A chlorine atom accepts one electron to form_______.

5. Sodium hydroxide is also called _______.

6. Bread, yogurt, and vinegar prepared through_______.

7. Now a days insulin and interferon are produced by _______.

8. The short name of an element is called_______.

9. Sponges have many_______ on their bodies.

10.Measl and Polio in man are caused by _______.


1. Bacteria which produce disease in plants and animals are called:a. Heterotrophic bacteriab. Autotrophic bacteriac. Parasitic bacteriad. Pathogenic bacteria

2. The steam which runs electric generator is a source of:

a. Nuclear energy b. wind energyc. Potential energy d. mechanical energy

3. Clouds of dust and gases in space are:a. Supernova b. Nebulac. Constellation d. Coma

4. The formula of calcium carbonate is:a. KCO3 b. K2CO3c. CuCO3 d. CaCO3

5. Sodium hydroxide solution in water will:a. Turn blue litmus redb. Give pink colour with phenolphthaleinc. Give red colour with methyl oranged. Not affect the phenolphthalein indicator

6. Which constituents present in air are used buy plants to prepare food?a. Nitrogen, water, carbon dioxide


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b. Oxygen, water, carbon dioxidec. Light, water, carbon dioxided. Light, nitrogen, water

7. Plants prepare their own food through photosynthesis are called:a. Parasites b. Saprotrophsc. Heterotrophs d. Autotrophs

8. In Pasteurization, milk is heated at:a. 62oC for half and hourb. 62oC for 15 secondsc. 71oC for half an hourd. 100oC for one minute

9. Which one does not exist as a molecule?:a. H2 b. Cl2c. Be d. Ne

10. The group of plants which includes plants without vascular tissue?a. Mosses b. Fernsc. Conifers d. Flowering plants


1. The melting points of covalent compounds are higher than those of ionic compound.

2. The distance between optical center and center of curvature is called the focallength.

3. In conifers, seeds are present in the fruit.

4. Phosphorus is added in soil in the form of super phosphate.

5. The symbol of an element is always taken from the English name of that element.

6. When a ray of light passes through a lens, it bends towards its thicker part.

7. Graphite is a bad conductor of electricity.

8. Carbon dioxide turns red litmus blue.

9. Spiny animals are only found in sea.

10.Convex is also called Converging lens.


No. Column (A) Column (B) Column (C)1. Antiseptic Hydrochloric acid2. Manufacture of

fertilizerCalcium hydroxide

3. Synthetic fibric Sodium hydroxide4. Making rayon Tartar emetic

5. Slaked lime Nitric acid6. Treatment of

blestringAmmoniumhydroxide

7. Function of thyroidglands

Rochelles salt

8. Softness of bread/Cake

Sulphric acid

9. laxative Baking soda10. Removing of poison

from the stomach.Potassium iodate


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Model Papers

Give Short answers.

1. Write down names of four diseases of man caused by viruses.

2. Define refraction of light.

3. Write down names of four bacterial diseases of man.

4. Give a definition of an acid.

5. Name the metal which continues burning in air.

6. What is approximate age of milky way galaxy?

7. Give three uses of Graphite.

8. On what factor does the liquid pressure depend?

Fill in the Blanks

AnswersNo.

Ans. No.

Ans. No.

Ans. No.

Ans.

1. minerals,water

2. (40%) 3. Caustic soda 4. Chloride

5. Caustic Soda 6. Fermentation

7. Geneticengineering

8. Symbol

9. Pores 10. Virus

Correct Answer

Answers

No. Ans. No. Ans. No. Ans. No. Ans.

1. c 2. a 3. b 4. d5. b 6. b 7. d 8. a9. d 10. d

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. F 2. F 3. T 4. T5. F 6. T 7. F 8. F

9. T 10. T

Match the ColumnsNo. Ans1. Hydrochloric Acid2. Nitric acid3. Sulphuric acid4. Sodium hydroxide5. Calcium hydroxide6. Ammonium

hydroxide7. Potassium iodate8. Baking soda9. Rochells salt10 Tartar emetic


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Short Questions1. i. Hepatitis B and C

ii. Polioiii. AIDSiv. Cold

2. When light passes from one transparent medium to another medium, it changes itsdirection. This is called refraction of light.

3. i. Typhoidii. Leprosyiii. T.Biv. Whooping cough

4. A substance which turns blue litmus paper red is called an acid.5. Magnesium (Mg)6. It is about 15 billion years.7. i. As a lubricant

ii. As a pigment in Paintsiii. In the form of graphite rods which are used as moderate in atomic reactors toreduce speed of neutrons.

8. The pressure exerted by a liquid depends upon its depth.


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Model Papers

PAPER 10

Subjective type the Questions

1. What is relationship between population and community?

2. Show the difference between diatomic and tri atomic molecule withexamples.

3. Complete the following equations and balance them.i. S+ ......... So3ii. Na2CO2+Hcl NaCl........CO2iii. Al + O2iv. Mg CO3 Heat ......+ CO2

v. K+..... Kcl

4. Write down the names of different groups of non-flowering plants.Describe salient features of each group and give examples.

Fill in the blanks.1. Micro means _______.

2. Cluster of stars is called _______.

3. Carbogen is used for _______ respiration.

4. Sodium is called _______ in Latin language.

5. Bases have _______ touch.

6. Carbon dioxide is _______ than air.

7. The depth at any point in a liquid is measured by the _______ from the point to thefree surface of the liquid living.

8. Viruses are considered as a link between living and_______ things. non-renewable.

9. The resources which can be regenerated with in short period are called_______.10.The rusting of iron is a _______ change.


1. The chemical name of lime stone is:a. Potassium carbonateb. Sodium carbonatec. Calcium carbonated. Barium carbonate

2. Viruses are considered as living organisms because:a. Can be crystallizedb. Can be observed with electronc. They are of different shapesd. They can reproduce

3. Which of the following group of plants consisting to thread like hyphae:a. Algae b. Fungic. Mosses d. Ferns

4. A ray parallel to principal axis, after refraction from convex lens:a. does not bendb. Passes through principal focusc. Passes through centre of curvatured. Passes through the middle of principal focus and center of curvature.

5. Cobalt is an element, its symbols is:a. C b. COc. Cu d. Co


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6. Which of the following is a hereditary disease?a. Influenza b. Hemophiliac. Small pox d. Dysentry

7. Which one does not exist as a molecule?a. H2 b. Cl2c. Be d. N2

8. The king of chemical is:a. KoH b. Hclc. H2SO4 d. NaCl

9. The compound used to Prepare glass is:a. Caustic soda b. Washing Sodac. Baking Soda d. NaCl

10. After which temperature water begins to expand on cooling:a. 0oC b. 30oCc. 4oC d. 15oC


1. Those Bacteria, which causes diseases in plants and animals are called pathogenicbacteria.

2. The process of transfer of characteristics is called variations.

3. New substances are always formed during a chemical change. These substanceshave usually different shape and composition.

4. Soap is prepared by heating together sodium hydroxide and vegetable oil or fat.

5. Cement is prepared by mixing stones, clay and potassium.

6. Animals without vertebral column are called invertebrates.

7. All bases are alkalies but all alkalies are not bases.

8. Mercury is also known as Hydragyrum.

9. Our solar system is in Orion orim.10.Gemstones are used as ornaments.


No. Column (A) Column (B) Column (C)1. Cuprous 32. Magnesium four electrons in

valence shell3. Ferric five electrons in

valence shell4. Phosphate +2

5. Nitrate six electron invalence shell

6. Carbonate +37. Carbon one electron in

valence shell8. Oxygen +19. Nitrogen 310. hydrogen 2

Give Short answers.

1. What are chromosomes composed of?

2. State three properties of acids.

3. What is shared pair of electrons?


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Model Papers

4. What are the uses of sulpher?5. Name three, mineral acids.6. How metamorphic rocks are formed?7. Write down of eight things used at home which are composed ofcarbon.8. Define Big Bang.

Fill in the Blanks

AnswersNo.

Ans. No. Ans. No.

Ans. No.

Ans.

1. Small 2. Constellation

3. Artificial 4. Natrium

5. Slippery 6. Heaviar 7. Pressure 8. Non living9. Non

renewable10. Chemical

Correct Answer

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. c 2. d 3. a 4. b5. d 6. b 7. c 8. c9. b 10. c

True /False

Answers

No.

Ans. No.

Ans.

No. Ans. No.

Ans.

1. T 2. F 3. T 4. T5. F 6. T 7. T 8. T

9. T 10. F

Match the ColumnsNo. Ans1. (+1)2. (+2)3. (+3)4. (3)5. (2)6. (3)7. Two electrons in valence

shell8. Six electrons in valence

shell9. Five electrons in valence

shell10 one electrons in valence

shell

Short Question1. Chromosomes are made of hereditary material called DNA.2. i. All acids have a soure taste

ii. All acids turn blue litmus solution red. They also turn methyl orange solution red.iii. Acids usually react with methods to produce salt and hydrogen gas.

3. The pair of electrons which exist between two atoms is called shared pair of electrons.4. Sulphur is used in the manufacture of Sulphuric acid which is further used in the

preparation of fertilizers, gun powder, refining of petroleum and steel industry.5. i. Hydrochloric acid Hcl

ii. Nitric acid HNO3


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iii. Sulphuric acid H2SO46. The rocks formed beneath the earth due to extreme pressure and temperature are

called metamorphic rocks.7. i. Pencil ii. comb

iii. Paper iv. Chairv. Wooden table vi. Body of T.Vvii. kerosene viii. Vegetable oil

8. A tremendous explosion at the beginning of the universe is called big bang.

sciences for class 8

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