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Questions:

Multiple Choice Question

98 x 1 = 98

Select the chemical equation which is unbalanced

(a)

NaOH + CO₂ → Na₂CO₃ + H₂O

(b)

CuSO₄ + H₂S → H₄SO₂ + CuS

(c)

2FeCl₃ + H₂S → 2FeCl₂ + 2HCl + S

(d)

2Mg + CO₂ → 2MgO + C

The symbol used to denote a liquid reactant or product in a reaction is

(a)

(s)

(b)

(aq)

(c)

(g)

(d)

(l)

Which of the following feature is common to both physical and chemical change?

(a)

Evolution of hydrogen gas

(b)

Formation of new precipitate

(c)

Evolution of carbon dioxide

(d)

Change in state and colour

If reaction between nitrogen and hydrogen to form ammonia is exothermic, then it will be accompanied by

(a)

Change in state

(b)

Change in colour

(c)

Evolution of heat

(d)

Formation of precipitate

A prism ABC (with BC as base) is placed in different orientations. A narrow beam of white light is incident on the prism as shown in Figure. In which of the following cases, after dispersion, the third colour from the top corresponds to the colour of the sky?

(a)

(i)

(b)

(ii)

(c)

(iii)

(d)

(iv)

A beam of light is incident through the holes on side A and emerges out of the holes on the other face of the box as shown in the figure. Which of the following could be inside the box?

(a)

Concave lens

(b)

Rectangular glass slab

(c)

Prism

(d)

Convex lens

A light ray enters from medium A to medium B as shown in Figure. The refractive index of medium B relative to A will be

(a)

greater than unity

(b)

less than unity

(c)

equal to unity

(d)

zero

Which of the following is the correct representation of electron dot structure of nitrogen?

(a)

(b)

(c)

(d)

A uniform magnetic field exists in the plane of paper pointing from left to right as shown in Figure. In the field an electron and a proton move as shown in the figure. The electron and the proton experience

(a)

Forces both pointing into the plane of paper

(b)

Forces both pointing out of the plane of paper

(c)

Forces pointing into the plane of paper and out of the plane of paper, respectively.

(d)

Force pointing opposite and along the direction of the uniform magnetic field respectively.

10.

The proper representation of series combination of cells obtaining maximum potential is

(a)

(b)

(c)

(d)

11.

Identify the circuit in which the electrical components have been properly connected.

(a)

(b)

(c)

(d)

12.

It is important to make small check dams across the flooded gullies because they
(i) hold water for irrigation
(ii) hold water and prevent soil erosion
(iii) recharge ground water
(iv) hold water permanently

(a)

(i) and (iv)

(b)

(ii) and (iii)

(c)

(iii) and (iv)

(d)

(ii) and (iv)

13.

Arabari forests of Bengal is dominated by

(a)

Teak

(b)

Sal

(c)

Banboo

(d)

Mangroove

14.

Select the wrong statement

(a)

Forests provide variety of products

(b)

Forests have greater plant diversity

(c)

Forests do not conserve soil

(d)

Forests conserve water

15.

Expand the abbreviation GAP

(a)

Governmental Agency for Pollution Control

(b)

Gross Assimilation by Photosynthesis

(c)

Ganga Action Plan

(d)

Governmental Agency for Animal Protection

16.

The three R's that will help us to conserve natural resources for long term use are

(a)

recycle, regenerate, reuse

(b)

reduce, regenerate, reuse

(c)

reduce, reuse, redistribute

(d)

reduce, recycle, reuse

17.

Which of the following statement is correct?

(a)

A person with myopia can see distant objects clearly

(b)

A person with hypermetropia can see nearby objects clearly

(c)

A person with myopia can see nearby objects clearly

(d)

A person with hypermetropia cannot see distant objects clearly

18.

The focal length of the eye lens increases when eye muscles

(a)

are relaxed and lens becomes thinner

(b)

contract and lens becomes thicker

(c)

are relaxed and lens becomes thicker

(d)

contract and lens becomes thinner

19.

The bluish colour of water in deep sea is due to

(a)

the presence of algae and other plants found in water

(b)

reflection of sky in water

(c)

scattering of light

(d)

absorption of light by the sea

20.

Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?

(a)

Dispersion of light

(b)

Scattering of light

(c)

Total internal reflection of light

(d)

Reflection of light from the earth

21.

Which of the following statements is correct regarding the propagation of light of different colours of white light in air?

(a)

Red light moves fastest

(b)

Blue light moves faster than green light

(c)

All the colours of the white light move with the same speed

(d)

Yellow light moves with the mean speed as that of the red and the violet light

22.

In which of the following, the image of an object placed at infinity will be highly diminished and point sized?

(a)

Concave mirror only

(b)

Convex mirror only

(c)

Convex lens only

(d)

Concave mirror, convex mirror, concave lens and convex lens

23.

A child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size and that of the legs smaller. The following is the order of combinations for the magic mirror from the top.

(a)

Plane, convex and concave

(b)

Convex, concave and plane

(c)

Concave, plane and concave

(d)

Convex, plane and concave

24.

You are given water, mustard oil, glycerine and kerosene. In which of these media a ray light incident obliquely at same angle would bend the most?

(a)

Kerosene

(b)

Water

(c)

Mustard oil

(d)

Glycerine

25.

In torches search lights and headlights of vehicles the bulb is placed

(a)

between the pole and the focus of the reflector

(b)

very near to the focus of the reflector

(c)

between the focus and centre of curvature of the reflector

(d)

at the centre of curvature of the reflector.

26.

A full length image of a distant tall building can definitely be seen by using.

(a)

a concave mirror

(b)

a convex mirror

(c)

a plane mirror

(d)

both concave as well as plane mirror

27.

Which of the following lenses would you prefer to use while reading small letters found in a dictionary?

(a)

A convex lens of focal length 50 cm

(b)

A concave lens of focal length 50 cm

(c)

A convex lens of focal length 5 cm

(d)

A concave lens of focal length 5 cm

28.

The change in focal length of eye lens is caused by action of

(a)

Pupil

(b)

Retina

(c)

Ciliary muscles

(d)

Iris

29.

The human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to

(a)

Presbyopia

(b)

Accommodation

(c)

Near sightedness

(d)

Far sightedness

30.

Disposable plastic plates should not be used because

(a)

They are made of materials with light weight

(b)

They are made of toxic materials

(c)

They are made of biodegradable materials

(d)

They are made of non-biodegradable materials

31.

What will happen if deer is missing in the food chain given below?
Grass \(\rightarrow\) Deer \(\rightarrow\)Tiger

(a)

The pollution of tiger increases

(b)

The pollution of grass decreases

(c)

Tiger will start eating grass

(d)

The pollution of tiger decreases and the pollution of grass increases

32.

Which of the statement is incorrect?

(a)

All green plants and blue green algae are producers

(b)

Green plants get their food from organic compounds

(c)

Producers prepare their own food from inorganic compounds

(d)

Plants convert solar energy into chemical energy

33.

In the following groups of materials, which group(s) contains only non-biodegradable items?
(1) Wood, paper, leather
(2) Polythene, detergent, PVC
(3) Plastic, detergent, grass
(4) Plastic, Bakelite, DDT

(a)

(b)

(c)

1 and 3

(d)

2 and 4

34.

Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as

(a)

eutrophication

(b)

pollution

(c)

biomagnification

(d)

accumulation

35.

Two pea plants one with round green seeds (RRyy) and another with wrinkled yellow (rrYY) seeds produce F₁ progeny that have round, yellow (RrYy) seeds. When F₁ plants are selfed, the F₂ progeny will have new combination of characters. Choose the new combination from the following:
(i) Round, yellow
(ii) Round, green
(iii) Wrinkled, yellow
(iv) Wrinkled, green

(a)

(i) and (ii)

(b)

(i) and (iv)

(c)

(ii) and (iii)

(d)

(i) and (iii)

36.

New species may be formed if
(i) DNA undergoes significant changes in germ cells
(ii) chromosome number changes in the gamete
(iii) there is no change in the genetic material
(iv) mating does not take place

(a)

(i) and (ii)

(b)

(i) and (iii)

(c)

(ii), (iii) and (iv)

(d)

(i), (ii) and (iii)

37.

Select the incorrect statement

(a)

Frequency of certain genes in a population change over several generations resulting in evolution.

(b)

Reduction in weight of the organism due to starvation is genetically controlled.

(c)

Low weight parents can have heavy weight progeny

(d)

Traits which are not inherited over generations do not cause evolution.

38.

Which one of the following does not increase while moving down the group of the periodic table?

(a)

Atomic radius

(b)

Metallic character

(c)

Valence

(d)

Number of shells in an element

39.

The element with atomic number 14 is hard and forms acidic oxide and a covalent halide. To which of the following categories does the element belong?

(a)

Metal

(b)

Metalloid

(c)

Non-metal

(d)

Left-hand side element

40.

Which of the following elements will form an acidic oxide?

(a)

An element with atomic number 7

(b)

An element with atomic number 3

(c)

An element with atomic number 12

(d)

An element with atomic number 19

41.

In human males, the testes lie in the scrotum because it helps in the

(a)

process of mating

(b)

formation of sperm

(c)

easy transfer of gametes

(d)

all the above

42.

A cross between a tall plant (TT) and short pea plant (tt) resulted in progeny that were all tall plants because

(a)

tallness is the dominant trait

(b)

shortness is the dominant trait

(c)

tallness is the recessive trait

(d)

height of pea plant is not governed by gene 'T' or 't'

43.

Which of the following statement are true for flowers?
(i)Flowers are always bisexual
(ii)They are the sexual reproductive organs
(iii)They are produced in all groups of plants
(iv)After fertilisation they give rise to fruits

(a)

(i) and (iv)

(b)

(ii) and (iii)

(c)

(i) and (iii)

(d)

(ii) and (iv)

44.

InRhizopus, tubular thread-like structures bearing sporangia at their tips are called

(a)

filaments

(b)

hyphae

(c)

rhizoids

(d)

roots

45.

Which of the given elements A, B, C, D and E with atomic number 2,3, 7, 10 and 30 respectively belong to the same period?

(a)

A,B,C

(b)

B,C,D

(c)

A,D,E

(d)

B,D,E

46.

Upto which element, the Law of Octaves was found to be applicable

(a)

Oxygen

(b)

Calcium

(c)

Cobalt

(d)

Potassium

47.

In Spirogyra, asexual reproduction takes place by

(a)

breaking up of filaments into smaller bits

(b)

division of a cell into two cells

(c)

division of a cell into many cells

(d)

formation of Young cells from older cells

48.

Characters transmitted from parents to offspring are present in

(a)

cytoplasm

(b)

ribosome

(c)

golgi bodies

(d)

genes

49.

The anther contains

(a)

sepals

(b)

ovules

(c)

carpel

(d)

pollen grains

50.

Which of the following is not a part of the female reproductive system in human beings?

(a)

Ovary

(b)

Uterus

(c)

Vas deferens

(d)

Fallopian

51.

An example of homologous organs is

(a)

Our arm and a dog's fore-leg

(b)

Our teeth and an elephant's tusks.

(c)

Potato and runners of grass.

(d)

all of the above

52.

Which of the following represents saponification reaction?

(a)

CH₃COONa + NaOH \(\xrightarrow [ ]{ CaO } \) CH₄ + Na₂CO₃

(b)

CH₃COOH + C₂H₅OH \(\xrightarrow [ ]{ H_2SO_4 } \) CH₃COOC₂H₅ + H₂O

(c)

2CH₃COOH + 2Na \(\rightarrow\) 2CH₃COONa + H₂

(d)

CH₃COOC₂H₅ + NaOH \(\rightarrow\) CH₃COONa + C₂H₅OH

53.

Ethanol reacts with sodium and forms two products. These are

(a)

sodium ethanoate and hydrogen

(b)

sodium ethanoate and oxygen

(c)

sodium ethoxide and hydrogen

(d)

UnAvailable Option

54.

Chlorine reacts with saturated hydrocarbons at room temperature in the

(a)

absence of sunlight

(b)

presence of sunlight

(c)

presence of water

(d)

presence of hydrochloric acid

55.

Buckminsterfullerene is an allotropic form of

(a)

Phosphorous

(b)

Sulphur

(c)

Carbon

(d)

Tin

56.

The strength of magnetic field inside a long current carrying straight solenoid is

(a)

More at the ends than at the centre

(b)

Minimum in the middle

(c)

Same at all points

(d)

Found to increase from one end to the other.

57.

Choose the incorrect statement

(a)

Fleming's right-hand rule is a simple rule to know the direction of induced current.

(b)

The right-hand thumb rule is used to find the direction of magnetic fields due to current carrying conductors.

(c)

The difference between the direct and alternating currents is that the direct current always flows in one direction, whereas the alternating current reverses its direction periodically.

(d)

In India, the AC changes direction after every 1/50 second.

58.

For a current in a long straight solenoid N- and S- poles are created at the two ends. Among the following statements, the incorrect statement is

(a)

The field lines inside the solenoid are in the form of straight lines which indicates that the magnetic field is the same at all points inside the solenoid

(b)

The strong magnetic field produced inside the solenoid can be used to magnetise a piece of magnetic material like soft iron, when placed inside the coil.

(c)

The pattern of the magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet.

(d)

The N- and S- Poles exchange position when the direction of current through the solenoid is reversed

59.

Choose the incorrect statement

(a)

We are encouraged to plant more trees so as to ensure clean environment and also provide biomass fuel.

(b)

Gobar-gas is produced when crops. vegetable wastes etc., decomposes in the absence of oxygen.

(c)

The main ingredient of biogas is ethane and it gives a lot of smoke and also produces a lot of residual ash.

(d)

Biomass is a renewable source of energy

60.

At the time of short circuit, the current in the circuit

(a)

reduces substantially

(b)

does not change

(c)

increases heavily

(d)

vary continuously

61.

The phenomenon of electromagnetic induction is

(a)

the process of charging a body.

(b)

the process of generating magnetic field due to a current passing through a coil.

(c)

producing induced current in a coil due to relative motion between a magnet and the coil.

(d)

the process of rotating a coil of an electric motor.

62.

Choose the event that does not occur in photosynthesis

(a)

Absorption of light energy by chlorophyll

(b)

Reduction of carbon dioxide to carbohydrates

(c)

Oxidation of carbon to carbon dioxide

(d)

Conversion of light energy to chemical energy

63.

Choose the correct statement?

(a)

Sun can be taken as an inexhaustible source of energy

(b)

There is infinite storage of fossil fuels inside the earth.

(c)

Hydro and wind energy plants are nonpolluting sources of energy.

(d)

Waste from a nuclear power plant can be easily disposed off.

64.

Which part of the solar cooker is responsible for greenhouse effect?

(a)

Coating with black colour inside the box

(b)

Mirror

(c)

Glass sheet

(d)

Outer cover of the solar cooker

65.

Ocean thermal energy is due to

(a)

Energy stored by waves in the ocean

(b)

Temperature difference at different levels in the ocean

(c)

Pressure difference at different levels in the ocean.

(d)

Tides arising out in the ocean.

66.

Which one of the following forms of energy leads to least environment pollution in the process of its harnessing and utilization?

(a)

Nuclear energy

(b)

Thermal energy

(c)

Solar energy

(d)

Geothermal energy

67.

Fuel used in thermal power plant is

(a)

Water

(b)

Uranium

(c)

Biomass

(d)

Fossil fuels

68.

Acid rain happen because

(a)

Sun leads to heating of upper layer of atmosphere

(b)

Burning of fossil fuels release oxides of carbon, nitrogen and sulphur in the atmosphere.

(c)

Electrical charges a produced due to friction among clouds

(d)

Earth's atmosphere contains acids.

69.

Which of the following property of a proton can change while it moves freely in a magnetic field ?

(a)

mass

(b)

speed

(c)

velocity

(d)

momentum

70.

A solar water heater cannot be used to get hot water on

(a)

A sunny day

(b)

A cloudy day

(c)

A hot day

(d)

A windy day

71.

An electric kettle consumes 1 Kw of electric power when operated at 220 V. A fuse wire of what rating must be used for it?

(a)

(b)

(c)

(d)

72.

In an electrical circuit three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness?

(a)

Brightness of all the bulbs will be the same

(b)

Brightness of bulb A will be the maximum

(c)

Brightness of bulb B will be more than that of A

(d)

Brightness of bulb B will be less than that of B

73.

The resistivity does not charge if

(a)

the material is charged

(b)

the temperature is charged

(c)

the shape of the resistor is charge

(d)

both material and temperature are changed

74.

Alloys are homogeneous mixtures of a metal with a metal or nonmetal. Which among the following alloys contain non-metal as one of its constituents?

(a)

Brass

(b)

Bronze

(c)

Amalgam

(d)

Steel

75.

2 ml each of concentrated HCl, HNO₃ and a mixture of concentrated HCl and concentrated HNO₃ in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occured in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be

(a)

(b)

(c)

(d)

76.

Stainless steel is very useful material for our life. In stainless steel, iron is mixed with

(a)

Ni and Cr

(b)

Cu and Cr

(c)

Ni and Cu

(d)

Cu and Au

77.

What happens when calcium is treated with water?

(i) It does not react with water.

(ii) It reacts violently with water.

(iii) It reacts less violently with water.

(iv) Bubbles of hydrogen gas formed stick to the surface of calcium.

(a)

(i) and (iv)

(b)

(ii) and (iii)

(c)

(i) and (ii)

(d)

(iii) and (iv)

78.

When a person is suffering from severe cold, he or she cannot

(a)

Differentiate the taste of an apple from that of an ice cream

(b)

differentiate the smell of a perfume from that of an agarbatti

(c)

Differentiate red light from green light

(d)

Differentiate a hot object from a cold object

79.

Which of the following is not an involuntary action?

(a)

Vomiting

(b)

Salivation

(c)

Heart beat

(d)

Chewing

80.

Which of the following statements about transmission of nerve impulse is incorrect?

(a)

Nerve impulse travels from dendritic end towards axonal end.

(b)

At the dendritic end electrical impulses bring about the release of some chemicals which generate an electrical impulse at the axonal end of another neutron.

(c)

The chemicals released from the axonal end of one neuron cross the synapse and generate a similar electrical impulse in a dendrite of another neuron.

(d)

A neuron transmits electrical impulses not only to another neuron but also to muscle and gland cells.

81.

The substance that triggers the fall of mature leaves and fruits from plants is due to

(a)

Auxin

(b)

Gibberellin

(c)

Abscissic acid

(d)

Cytokinin

82.

Growth of pollen tubes towards ovules is an example of

(a)

Hydrotropism

(b)

Chemotropism

(c)

Geotropism

(d)

Phototropism

83.

Select the mis-matched pair.

(a)

Adrenaline : Pituitary gland

(b)

Testosterone : Testes

(c)

Estrogen : Ovary

(d)

Thyroxin : Thyroid gland

84.

Choose the incorrect statement about insulin.

(a)

It is produced from pancreas

(b)

It regulates growth and development of the body

(c)

It regulates blood sugar level

(d)

Insufficient secretion of insulin will cause diabetes

85.

The gap between two neurons is called as

(a)

Dendrite

(b)

Synapse

(c)

Axon

(d)

Impulse

86.

Select the correct statement

(a)

Heterotrophs do not synthesise their own food

(b)

Heterotrophs utilise solar energy for photosynthesis

(c)

Heterotrophs synthesise their own food

(d)

Heterotrophs are capable of converting carbon dioxide and water into carbohydrates

87.

The commonly used safety fuse wire is made of

(a)

Lead

(b)

Copper

(c)

Nickel

(d)

An alloy of tin and lead

88.

The autotrophic mode of nutrition requires

(a)

Carbon dioxide and water

(b)

Chlorophyll

(c)

Sunlight

(d)

All of the above

89.

The xylem in plants is responsible for

(a)

Transport of water

(b)

Transport of food

(c)

Transport of amino acids

(d)

Transport of oxygen

90.

Which of the following pairs will give displacement reactions?

(a)

NaCl solution and copper metal

(b)

MgCl₂ solution and aluminium metal

(c)

FeSO₄ solution and silver metal

(d)

AgNO₃ solution and copper metal

91.

Which of the following are present in a dilute aqueous solution of hydrochloric acid?

(a)

\(H_3O^++CH^-\)

(b)

\(H_3O^++OH^-\)

(c)

\(Cl^-+OH^-\)

(d)

unionised HCl

92.

Which of the following statement is not correct?

(a)

All metal carbonates react with acid to give a salt, water and carbon dioxide

(b)

All metal oxides react with water to give salt and acid

(c)

Some metals react with acids to give salt and hydrogen

(d)

Some non-metal oxides react with water to form an acid

93.

In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

(a)

Lead sulphate (insoluble)

(b)

Ammonium nitrate

(c)

Lead acetate

(d)

Potassium sulphate

94.

Which of the following substance will not give carbon dioxide on treatment with dilute acid?

(a)

Marble

(b)

Limestone

(c)

Baking soda

(d)

Lime

95.

Sodium carbonate is a basic salt because it is a salt of

(a)

Strong acid and strong base

(b)

weak acid and weak base

(c)

strong acid and weak base

(d)

weak acid and strong base

96.

What happens when a solution of an acid is mixed with a solution of a base in a test tube?

(a) The temperature of the solution increases

(b) The temperature of the solution decreases

(d) Salt formation takes place

(a)

(i) only

(b)

(i) and (iii)

(c)

(ii) and (iii)

(d)

(i) and (iv)

97.

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation?

(a)

KMnO₄ is an oxidising agent, it oxidises FeSO₄

(b)

FeSO₄ acts as an oxidising agent and oxidises KMnO₄

(c)

The colour disappears due to dilution; no reaction is involved

(d)

KMnO₄ is an unstable compound and decomposes in presence of FeSO₄ to a colourless compound.

98.

Which of the following statements about the given reaction are correct?
3Fe(s) + 4H₂O(g) \(\rightarrow\) Fe₃O₄(s) + 4H₂(g)
(i) Iron metal is getting oxidised
(ii) Water is getting reduced
(iii) Water is acting as reducing agent
(iv) Water is acting as oxidising agent

(a)

(i), (ii) and (iii)

(b)

(iii) and (iv)

(c)

(i), (ii) and (iv)

(d)

(ii) and (iv)

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Answers Key:

Multiple Choice Question

98 x 1 = 98

(a)
NaOH + CO₂ → Na₂CO₃ + H₂O

(d)
(l)

(d)
Change in state and colour

(b)
(ii)

(d)
Convex lens

(a)
greater than unity

10.

11.

12.

(b)
(ii) and (iii)

13.

(b)
Sal

14.

15.

16.

(d)
reduce, recycle, reuse

17.

18.

(a)
are relaxed and lens becomes thinner

19.

20.

(b)
Scattering of light

21.

22.

(d)
Concave mirror, convex mirror, concave lens and convex lens

23.

24.

(d)
Glycerine

25.

(b)
very near to the focus of the reflector

26.

(b)
a convex mirror

27.

28.

29.

(b)
Accommodation

30.

(d)
They are made of non-biodegradable materials

31.

(d)
The pollution of tiger decreases and the pollution of grass increases

32.

(b)
Green plants get their food from organic compounds

33.

(d)
2 and 4

34.

35.

(b)
(i) and (iv)

36.

(a)
(i) and (ii)

37.

(b)
Reduction in weight of the organism due to starvation is genetically controlled.

38.

39.

(b)
Metalloid

40.

(a)
An element with atomic number 7

41.

(b)
formation of sperm

42.

(a)
tallness is the dominant trait

43.

(d)
(ii) and (iv)

44.

(b)
hyphae

45.

(b)
B,C,D

46.

(b)
Calcium

47.

(a)
breaking up of filaments into smaller bits

48.

(d)
genes

49.

(d)
pollen grains

50.

51.

(d)
all of the above

52.

(d)
CH₃COOC₂H₅ + NaOH \(\rightarrow\) CH₃COONa + C₂H₅OH

53.

54.

(b)
presence of sunlight

55.

56.

57.

(d)
In India, the AC changes direction after every 1/50 second.

58.

(c)
The pattern of the magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet.

59.

60.

61.

62.

63.

(a)
Sun can be taken as an inexhaustible source of energy

64.

65.

(b)
Temperature difference at different levels in the ocean

66.

67.

(d)
Fossil fuels

68.

(b)
Burning of fossil fuels release oxides of carbon, nitrogen and sulphur in the atmosphere.

69.

(d)
momentum

70.

(b)
A cloudy day

71.

(d)
5A

72.

73.

74.

(d)
Steel

75.

(b)
Au

76.

(a)
Ni and Cr

77.

(d)
(iii) and (iv)

78.

(b)
differentiate the smell of a perfume from that of an agarbatti

79.

(d)
Chewing

80.

(b)
At the dendritic end electrical impulses bring about the release of some chemicals which generate an electrical impulse at the axonal end of another neutron.

81.

82.

(b)
Chemotropism

83.

(a)
Adrenaline : Pituitary gland

84.

(b)
It regulates growth and development of the body

85.

(b)
Synapse

86.

(a)
Heterotrophs do not synthesise their own food

87.

(a)
Lead

88.

(d)
All of the above

89.

(a)
Transport of water

90.

(d)
AgNO₃ solution and copper metal

91.

(a)
\(H_3O^++CH^-\)

92.

(b)
All metal oxides react with water to give salt and acid

93.

(b)
Ammonium nitrate

94.

(d)
Lime

95.

(d)
weak acid and strong base

96.

(d)
(i) and (iv)

97.

(a)
KMnO₄ is an oxidising agent, it oxidises FeSO₄

98.

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