Narayana Group CBSE Mains Examination Question Paper : narayanadelhi.com

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Exam : CBSE Mains Examination
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Narayana CBSE Mains Examination Question Paper

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Chemistry

1. Following compounds are given:
(a) CH3CH2OH
(b) CH3COCH3
(c) 3 CH — CHOH
|
CH3
(d) CH3OH
Which of the above compound(s), on being warmed with iodine solution and NaOH, will give iodoform?
Options:
(1) (a), (b) and (c)
(2) (a) and (b)
(3) (a), (c) and (d)
(4) only (b)

Ans. (1)
2. Match List-I (substances) with List-II (processes) employed in the manufacture of the substances and select the correct option
List-I List-II
Substances Processes
(a) Sulphuric (i) Haber’s acid Process
(b) Steel (ii) Bessemers’ Process
(c) Sodium (iii) Leblanc hydroxide Process
(d) Ammonia (iv) Contact Process
Options:
(a) (b) (c) (d)
1. (iv) (iii) (ii) (i)
2. (iv) (ii) (iii) (i)
3. (i) (iv) (ii) (iii)
4. (i) (ii) (iii) (iv)
Ans. (2)

3. Fructose reduces Tollen’s reagent due to:
(1) secondary alcoholic group
(2) enolisation of fructose followed by conversion to aldehyde by base.
(3) asymmetric carbons
(4) primary alcoholic group
Ans. (2)

4. Which of the following oxidation states is the most common among the lanthanoids?
(1) 5
(2) 3
(3) 4
(4) 2
Ans. (2)

6. Among the following four compounds the acidity order is:
(a) phenol
(b) methyl phenol
(c) metanitrophenol
(d) paranitrophenol
(1) a > d > c > b
(2) b > a > c > d
(3) d > c > a > b
(4) c > d > a > b
Ans. (3)

7. A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be
(h = 6.6 × 10–34 Js) :
(1) 1.0 × 10–35 m
(2) 1.0 × 10–32 m
(3) 6.6 × 10–32 m
(4) 6.6 × 10–34 m
Ans. (1)

8. Which of the following conformers for ethylene glycol is most stable?
Ans. (2)
9. When glycerol is treated with excess of HI, it produces
(1) propene
(2) glycerol triiodide
(3) 2-iodopropane
(4) allyl iodide
Ans. (3)

10. Some statements about heavy water are given below:
(a) Heavy water is used as moderator in nuclear reactors.
(b) Heavy water is more associated than ordinary water.
(c) Heavy water is more effective solvent than ordinary water.
Which of the above statements are correct?
(1) (b) and (c)
(2) (a) and (c)
(3) (a) and (b)
(4) (a), (b) and (c)
Ans. (2)

11. Some of the properties of the two species, NO3 – and H3O+ are described below. Which one of them is correct ?
(1) Isostructural with different hybridization for the central atom
(2) Similar in hybridization for the central atom with different structures
(3) Dissimilar in hybridization for the central atom with different structures.
(4) Isostructural with same hybridization for the central atom
Ans. (3)

Botany

31. Consider the following four statements A, B, C and D and select the right option for two correct statements.
Statements :
(A) In vexillary aestivation, the large posterior petal is called – standard, two lateral ones are wings and-two small anterior petals are termed keel.
(B) The floral formula for Liliaceae is
(C) In pea flower the stamens are monoadelphous
(D) The floral formula for Solanaceae is O+K(3)C(3)A(4)G(2)
The correct statements are :
(1) (B)and(C )
(2) (C)and(D)
(3) (A)and(C)
(4) (A) and (B)
Ans. (4)

32. ABO blood grouping is controlled by gene I which has three alleles and show co-dominance. There are six genotypes. How many phenotypes in all are possible?
(1) Four
(2) Five
(3) Six
(4) Three
Ans. (1)

33. Study the pedigree chart of a certain family given below and select the correct conclusion which can be drawn for the character.
(1) The trait under study could not be colourblindness
(2) The male parent is homozygous dominant
(3) The female parent is heterozygous
(4) The parents could not have had a normal daughter for this character
Ans. (3)

34. Three of the following statements about enzymes are correct and one is wrong.?
Which one is wrong ?
(1) Enzymes are highly specific
(2) Most enzymes are proteins but some are lipids
(3) Enzymes require optimum pH for maximal activity
(4) Enzymes are denatured at high temperatures but in certain exceptional organisms they are effective even at temperatures 80° – 90°C.
Ans. (2)

35. Select the correct combination of the statements
(a-d) regarding the characteristics of certain organisms :
(a) Methanogens are Archaebacteria produce methane in marshy areas
(b) Nostoc is a filamentous blue-green alga which fixes atmospheric nitrogen
(c) Chemosynthetic autotrophic bacteria synthesize cellulose from glucose
(d) Mycoplasma lack a cell wall and can survive without oxygen
The correct statements are :
(1) (b), (c), (d)
(2) (a), (b), (d)
(3) (b), (c)
(4) (a),(b),(c)
Ans. (2)

36. Identify the components labelled A, B, C and D in the diagram below from the list (i) to (viii) given along with.
Components :
(i) Cristae of mitochondria
(ii) Inner membrane of mitochondria
(iii) Cytoplasm
(iv) Smooth endoplasmic reticulum
(v) Rough endoplasmic reticulum
(vi) Mitochondrial matrix
(vii) Cell vacuole
(viii) Nucleus
The correct components are :
A B C D
(1) (vi) (v) (iv) (vii)
(2) (v) (i) (iii) (ii)
(3) (v) (iv) (viii) (iii)
(4) (i) (iv) (viii) (vi)
Ans. (3)

37. Signals from fully developed foetus and placenta ultimately lead to parturition which requires the release of :
(1) Oxytocin from foetal pituitary
(2) Relaxin from placenta
(3) Estrogen from placenta
(4) Oxytocin from maternal pituitary
Ans. (4)

38. Examine the figures A, B, C and D. In which one of the four options all the items, A, B, C and D are correct ?
Options :
A B C D
1 Selaginella Equisetum Salvinia Ginkgo
2 Funaria Adiantum Salvinia Riccia
3 Chara Marchantia Fucus Pinus
4 Equisetum Ginkgo Selaginella Lycopodium
Ans. (1)

39. Which one of the following is the correct description of a certain part of a normal human skeleton ?
(1) The 9th and 10th pairs of ribs are called the floating ribs
(2) Glenoid cavity is a depression to which the thigh bone articulates
(3) Parietal bone and the temporal bone of the skull are joined by fibrous joint
(4) First vertebra is axis which articulates with the occipital condyles
Ans. (3)

40. Root development is promoted by :
(1) Gibberellin
(2) Ethylene
(3) Abscisic acid
(4) Auxin
Ans. (4)

Zoology

61. If for some reason the parietal cells of the gut epithelium become partially non-functional, what is likely to happen ?
(1) Steapsin will be more effective
(2) Proteins will not be adequately hydrolysed by pepsin into proteoses and peptones
(3) The pancreatic enzymes and specially the trypsin and lipase will not work efficiently
(4) The pH of stomach will fall abruptly
Ans. (2)

62. An elaborate network of filamentous proteinaceous structures present in the cytoplasm which helps in the maintenance of cell shape is called :
(1) Plasmalemma
(2) Cytoskeleton
(3) Thylakoid
(4) Endosplasmic Reticulum
Ans. (2)

63. Jaundice is a disorder of :
(1) Digestive system
(2) Circulatory system
(3) Excretory system
(4) Skin and eyes
Ans. (1)

65. An example of endomycorrhiza is
(1) Agaricus
(2) Rhizobium
(3) Nostoc
(4) Glomus
Ans. (4)

66. One of the commonly used plant growth hormone in tea plantations is :
(1) Zeatin
(2) Indole -3 – acetic acid
(3) Ethylene
(4) Abscisic acid
Ans. (2)

67. Transport of food material in higher plants takes place through :
(1) Tracheids
(2) Sieve elements
(3) Companion cells
(4) Transfusion tissue
Ans. (2)

69. Given below are four statements (A-D) each with one or two blanks. Select the option which correctly fills up the blanks in two statements :
Statements :
(A) Wings of butterfly and birds look alike and are the results of __(i)__ , evolution
(B) Miller showed that CH4, H2, NH3 and __(i)__, when exposed to electric discharge in a flask resulted in formation of ___(ii)__ .
(C) Vermiform appendix is a __(i)__ organ and an ___(ii)__ evidence of evolution
(D) According to Darwin evolution took place due to __(i)__ and __(ii)__ of the fittest.
Options :
(1) (B) – (i) water vapour (ii) amino acids,
(C) – (i) rudimentary (ii) anatomical
(2) (C) – (i) vestigial, (ii) anatomical,
(D) – (i) mutations (ii) multiplication
(3) (D) – (i) small variations, (ii) survival,
(A) – (i) convergent
(4) (A) – (i) convergent,
(B) – (i) oxygen, (ii) nucleosides
Ans. (3)

70. Fastest distribution of some injectible material/ medicine and with no risk of any kind can be achieved by injecting it into the :
(1) veins
(2) lymph vessels
(3) muscles
(4) arteries
Ans. (1)

Physics

91. The Magnetic moment of a diamagnetic atom is:
(1) between zero and one
(2) equal to zero
(3) much greater than one
(4) 1
Ans. (2)

92. If cp and cv denote the specific heats (per unit mass) of an ideal gas of molecular weight M.
(1) cp – cv = R/M
(2) cp – cv = MR
(3) Cp – cv = R/M
(4) cp – cv = R
where R is the molar gas constant
Ans. (1)

93. The thermo e.m.f. E in volts of a certain thermocouple is found to vary with temperature difference ? in °C between the two junctions according to the relation
The neutral temperature for the thermo-couple will be:
(1) 225°C
(2) 30°C
(3) 450°C
(4) 400°C
Ans. (1)

94. (a) Centre of gravity (C.G.) of a body is the point at which the weight of the body acts.
(b) Centre of mass coincides with the centre of gravity if the earth is assumed to have infinitely large radius.
(c) To evaluate the gravitational field intensity due to any body at an external point, the entire mass of the body can be considered to be concentrated at its C.G.
(d) The radius of gyration of any body rotating about an axis is the length of the perpendicular dropped from the C.G. of the body to the axis.
Which one of the following pairs of statements is correct?
(1) (b) and (c)
(2) (c) and (d)
(3) (d) and (a)
(4) (a) and (b)
Ans. (4)

100. A solid cylinder and a hollow cylinder, both of the same mass and same external diameter are released from the same height at the same time on an inclined plane. Both roll down without slipping. Which one will reach the bottom first?
(1) Hollow cylinder
(2) Solid cylinder
(3) Both together only when angle of inclination of plane is 45°
(4) Both together

106. When monochromatic radiation of intensity I falls on a metal surface, the number of photoelectron and their maximum kinetic energy are N and T respectively. If the intensity of radiation is 2I, the number of emitted electrons and their maximum kinetic energy are respectively:
(1) 2N and 2T
(2) N and T
(3) N and 2T
(4) 2N and T
Ans. (4)

107. A particle moves in x–y plane according to rule x = a sin?t and y = cos?t. The particle follows:
(1) a parabolic path:
(2) a straight line path inclined equally to x and y-axis.
(3) an elliptical path
(4) a circular path
Ans. (4)

108. Two parallel metal plates having charges +Q and –Q face each other at a certain distance between them. If the plates are now dipped in kerosene oil tank, the electric field between the plates will
(1) decrease
(2) remain same
(3) become zero
(4) increase
Ans. (1)

110. A ray of light is incident on a 60° prism at the minimum deviation position. The angle of refraction at the first face (i.e., incident face) of the prism is:
(1) 45°
(2) 60°
(3) zero
(4) 30°
Ans. (4)