Q3
mcq
1 mark
Triple covalent bond is found in :
- A. $C_6H_6$
- B. $C_2H_4$
- C. $C_3H_4$
- D. $CH_3CHO$
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Q4
mcq
1 mark
Which of the following oxide(s) is/are soluble in water to form alkali/alkalies ?
(i) $SO_2$
(ii) $Na_2O$
(iii) $NO_2$
(iv) $K_2O$
- A. (ii) and (iv)
- B. Only (iii)
- C. (i), (ii) and (iv)
- D. Only (iv)
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Q4
mcq
Which of the following oxide(s) is/are soluble in water to form alkali/alkalies?
- A. (ii) and (iv)
- B. Only (iii)
- C. (i), (ii) and (iv)
- D. Only (iv)
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Q5
mcq
1 mark
Carbon dioxide gas is not produced when hydrochloric acid reacts with :
- A. Limestone
- B. Lime water
- C. Baking Soda
- D. Marble
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Q6
mcq
1 mark
In the process of galvanisation of iron, the metal used for the coating over iron is :
- A. Aluminium
- B. Gallium
- C. Zinc
- D. Lead
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Q7
mcq
1 mark
The carbon compound having functional group is :
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Q8
mcq
The inner lining of stomach is protected from hydrochloric acid by:
- A. Bile
- B. Mucus
- C. Pepsin
- D. Saliva
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Q9
mcq
Select the correct statement from the following:
- A. Trypsin digests proteins, whereas lipase digests carbohydrates.
- B. Trypsin digests carbohydrates, whereas lipase digests proteins.
- C. Trypsin digests emulsified fats, whereas lipase digests proteins.
- D. Trypsin digests proteins, whereas lipase digests emulsified fats.
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Q10
mcq
Spinal cord originates from:
- A. Cerebellum
- B. Pons
- C. Hypothalamus
- D. Medulla
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Q11
mcq
Select the mismatched pair:
- A. Adrenal gland — Adrenaline
- B. Thyroid gland — Thyroxin
- C. Pituitary gland — Insulin
- D. Ovary — Estrogen
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Q12
mcq
Select from the following, a disease which is not transmitted sexually:
- A. Gonorrhoea
- B. Tuberculosis
- C. HIV-AIDS
- D. Syphilis
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Q13
mcq
Potential difference can also be represented as:
- A. Work done / Charge
- B. Work done / Charge
- C. Work done / (Charge Time)
- D. Work done / Charge / Time
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Q14
mcq
Two LED bulbs of 12 W and 6 W are connected in series. If the current flowing through 6 W bulbs is 0005 A, the current that flows through 12 W bulb is:
- A. 0005 A
- B. 0 01 A
- C. 00025 A
- D. 0 02 A
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Q15
mcq
According to the International colour coding, wires used in electrical appliances which require earthing are:
- A. Live is brown; Neutral is blue and Earth is black
- B. Live is brown; Neutral is blue and Earth is green
- C. Live is red; Neutral is green and Earth is blue
- D. Live is red; Neutral is green and Earth is black
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Q16
mcq
From a power station, the power is transmitted to distant places in the form of AC at a very high voltage because:
- A. electricity is less dangerous at high voltages.
- B. electricity is generated at high voltage.
- C. transmission is faster at high voltages.
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Q17
mcq
Assertion (A): Ethyne is widely used for cutting and welding iron and steel.
Reason (R): Ethyne is an unsaturated hydrocarbon involving carbon-to-carbon triple bond.
- A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of the Assertion (A).
- B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- C. Assertion (A) is true, but Reason (R) is false.
- D. Assertion (A) is false, but Reason (R) is true.
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Q18
mcq
Assertion (A): ATP is the energy currency for most of the cellular processes.
Reason (R): Endothermic processes in the cell use ATP to carry out reactions.
- A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of the Assertion (A).
- B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- C. Assertion (A) is true, but Reason (R) is false.
- D. Assertion (A) is false, but Reason (R) is true.
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Q19
mcq
Assertion (A): Pancreas produces a hormone called insulin.
Reason (R): Insulin increases the blood sugar level in the human body.
- A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of the Assertion (A).
- B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- C. Assertion (A) is true, but Reason (R) is false.
- D. Assertion (A) is false, but Reason (R) is true.
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Q20
mcq
Assertion (A): A current carrying straight solenoid, when suspended freely rests in geographical north-south direction.
Reason (R): Earth behaves as a huge magnet which has the north pole towards the geographical south, whereas the current carrying solenoid behaves like a bar magnet.
- A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of the Assertion (A).
- B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- C. Assertion (A) is true, but Reason (R) is false.
- D. Assertion (A) is false, but Reason (R) is true.
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Q21
short answer
2 marks
Give one example of the reaction in which: (a) (i) a more reactive metal displaces a less reactive metal from its aqueous salt solution and the colour of the solution changes. (ii) an insoluble precipitate is formed. 2 OR (b) When a zinc plate is dipped in ferrous sulphate solution for some time, it is observed that the pale green colour of the solution disappears. (i) Explain the observation. (ii) Write the chemical equation for the reaction taking place.
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Q22
short answer
2 marks
Name the site of complete digestion in the human body and write the name of the end products formed of (i) carbohydrates, (ii) fats, and (iii) proteins. 2
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Q23
short answer
2 marks
Give an example of a plant hormone that promotes growth. Explain how this hormone promotes the growth of tendril around a support. 2
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Q24
short answer
2 marks
Pancreas has dual nature. Justify this statement with an example. 2
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Q25
short answer
2 marks
(a) A student cannot see distinctly the charts hanging in the science laboratory. Name the defect of vision he/she is suffering from. List two causes of this defect. Suggest the type of lenses for the modification of this defect. 2 OR (b) A person cannot see distinctly the objects placed at the least distance of distinct vision for a normal eye. However, he can easily read a newspaper by placing it at a distance of 40 cm from his eyes. Name the defect of vision in this case. List its two causes. Suggest the type of lenses for his spectacles. 2
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Q26
short answer
2 marks
Name two non-biodegradable substances. In the following food chain, maximum concentration of harmful non-biodegradable chemicals was found in the bodies of hawks. Why? Grass Rabbits Snakes Hawks 2
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Q27
long answer
3 marks
Consider the types of reaction mentioned below in (i) and (ii) : (i) AB + C2B A(BC)2 (ii) ABO3 AO + BO2 (a) Identify the types of reactions mentioned in the chemical equations (i) and (ii). (b) Give one example for each type of reaction in the form of word equation or chemical equation. 3
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Q28
long answer
3 marks
You have three test tubes containing three colourless solutions such as sodium sulphuric acid, hydrochloric acid and sodium sulphate solution. You also have pH paper strips. (a) How will you identify these three solutions using pH paper strips? (b) Which two of these solutions will form acidic solution when mixed in the proper amount? (c) Write the chemical equation for the reaction that will take place between the two solutions mentioned in (b). 3
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Q28
short answer
3 marks
You have three test tubes containing three colourless liquids, say conc. sulphuric acid, conc. solution of sodium hydroxide and conc. solution of sodium sulphate. You also have strips of pH paper.
(a) How would identify these three liquids using pH paper strips?
(b) Which two liquids, when mixed together in proper quantities can form a neutral salt solution?
(c) Write the chemical equation for the reaction that will occur between the two liquids mixed in (b).
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Q29
long answer
3 marks
(a) List the three events that occur during the process of photosynthesis in plants. 3 OR (b) What is lymph? What is the difference between lymph and blood plasma? List two functions of lymph. 3
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Q29
short answer
3 marks
(a) List three events that occur during the process of photosynthesis in plants.
OR
(b) What is lymph ? How is lymph different from blood plasma in composition ? List two functions of lymph.
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Q30
short answer
3 marks
A candle flame is placed at a distance of 18 cm from the optical centre of a convex lens. If its image is formed on a screen placed at a distance of 36 cm from the lens, answer the following questions:
(a) What is the magnification of the image formed?
(b) What is the focal length of the lens? Use the Lens Formula to determine it.
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Q31
short answer
3 marks
(a) Define the following terms in the context of spherical mirrors:
(i) Pole
(ii) Centre of curvature
(iii) Principal axis
(iv) Principal focus
(b) An object is placed at a distance of 60 cm from the pole of a concave mirror. If its real and inverted image is formed on a screen placed at a distance of 60 cm in front of the mirror, what is the focal length of the mirror? Give justification for your answer.
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Q31
short answer
3 marks
b) An object is placed at a distance of 60 cm from the pole of a concave mirror. If its real and inverted image is formed on a screen placed at a distance of 60 cm in front of the mirror, what is the focal length of the mirror? Give justification for your answer.
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Q32
short answer
3 marks
(a) State Ohms law. List two factors on which the resistance of a cylindrical conductor at a given temperature depends. A wire was drawn into a wire of double its length by melting it. If the resistance of the old wire was $R$, what is the resistance of the new wire?
OR
(b) (i) Write the formula for finding the value of the equivalent resistance of three resistors of resistance $R_1$, $R_2$ and $R_3$, when the resistors are connected in (i) series, and (ii) parallel.
(ii) List two advantages of connecting electrical devices in parallel with the source of electricity instead of connecting them in series.
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Q32
short answer
3 marks
a) State Ohm's law. List two factors on which the resistance of a cylindrical conductor at a given temperature depends. A wire was drawn into a wire of double its length by melting it. If the resistance of the old wire was $R$, what is the resistance of the new wire?
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Q32
short answer
3 marks
b) (i) Write the formula for finding the value of the equivalent resistance of three resistors of resistance $R_1$, $R_2$ and $R_3$, when the resistors are connected in (i) series, and (ii) parallel. (ii) List two advantages of connecting electrical devices in parallel with the source of electricity instead of connecting them in series.
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Q33
short answer
3 marks
Define ecosystem. List two artificial (man-made) ecosystems. Natural ecosystems like forests and lakes do not require regular cleaning, whereas the artificial ecosystems start giving foul smell when not cleaned regularly.
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Q34
long answer
5 marks
a) Write the molecular formula of methane and ethane, stating the general formula of the homologous series to which these compounds belong. What is the difference in the molecular mass in between the two successive members of a homologous series?
(b) Write the name and molecular formula of an alcohol having two carbon atoms in its molecule. Write balanced chemical equation to indicate what happens when this compound is heated at 443 K with excess conc. H$_2$SO$_4$. Name the main product formed in the reaction stating the function of conc. H$_2$SO$_4$ in the reaction.
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Q34
long answer
5 marks
a) How do the following conversions take place? Write chemical equation for each:
(i) Ethanol to Ethanoic acid
(ii) Ethene to Ethane
(b) Give one example each with chemical equation for the following reactions:
(i) Combustion reaction
(ii) Substitution reaction
(iii) Saponification reaction
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Q35
long answer
5 marks
a) What is regeneration? Which types of cells are used by such multicellular organisms to regenerate? Name the organism which exhibits this process.
(b) State one function of each of the following parts of the human male reproductive system:
(i) Vas deferens
(ii) Testes
(iii) Prostate glands
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Q36
short answer
5 marks
a) What is meant by solenoid? When an electric current is passed through a long, hollow and straight solenoid, what magnetic field is produced? Where is the strength of this magnetic field maximum and why?
(b) Write Fleming's left-hand rule. Use this rule to solve the following problem: A straight conductor is placed in an east-west direction in a uniform magnetic field. If on passing electric current through the conductor from east to west, the conductor moves towards north, then what is the direction of the magnetic field?
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Q36
long answer
5 marks
(a) What is meant by pollination? Name and differentiate between the two types of pollination.
(b) What happens to the pollen which falls on a suitable stigma?
(c) Mention the post-fertilisation changes that occur in (i) Ovary and (ii) Ovule in the flower.
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When a ray of light moving in a medium enters obliquely in another medium, it bends from its path. This phenomenon is called refraction of light. The ability of a medium to refract light is expressed in terms of optical density. The term optical density is not the same as mass density. If we compare two optical media, the one with the larger absolute refractive index is an optically denser medium than the other. Also, the speed of light through a given medium is inversely proportional to its optical density.
Q37
short answer
1 mark
When a ray of light moving in a medium enters obliquely in another medium, it bends from its path. This phenomenon is called refraction of light. The ability of a medium to refract light is expressed in terms of optical density. The term optical density is not the same as mass density. If we compare two optical media, the one with the larger absolute refractive index is an optically denser medium than the other. Also, the speed of light through a given medium is inversely proportional to its optical density.
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The melting points and the boiling points of ionic compounds are comparatively much higher than that of the covalent compounds. The ionic compounds are so called because they are formed by the transfer of electrons from a metal to a non-metal. In the ionic compounds, the transfer of electrons from one element to the other is controlled by their electronic configurations. It is because every element tends to attain a completely filled valence shell of its nearest noble gas or a stable octet.
Q38
long answer
The melting points and the boiling points of ionic compounds are comparatively much higher than that of the covalent compounds. The ionic compounds are so called because they are formed by the transfer of electrons from a metal to a non-metal. In the ionic compounds, the transfer of electrons from one element to the other is controlled by their electronic configurations. It is because every element tends to attain a completely filled valence shell of its nearest noble gas or a stable octet.
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When a ray of light moving in a medium enters obliquely in another medium, it bends from its path. This phenomenon is called refraction of light. The ability of a medium to refract light is expressed in terms of optical density. The term optical density is not the same as mass density. If we compare two optical media, the one with the larger absolute refractive index is an optically denser medium than the other. Also, the speed of light through a given medium is inversely proportional to its optical density.
Q45
short answer
1 mark
Define the term absolute refractive index of a medium.
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Q46
short answer
1 mark
Refractive indices of glass, water and carbon disulphide are 150, 133 and 162 respectively. In which one of these media is the speed of light (i) highest, and (ii) lowest?
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Q47
short answer
2 marks
The absolute refractive indices of glass and water are $\frac{3}{2}$ and $\frac{4}{3}$ respectively. If the speed of light in water is $2.25 \times 10^8$ m/s, find the speed of light in (I) vacuum, and (II) glass.
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Q48
short answer
2 marks
The absolute refractive indices of glass and water are $\frac{3}{2}$ and $\frac{4}{3}$ respectively. Find the refractive index of water with respect to glass.
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Q50
short answer
1 mark
The atomic number of sodium is 11. Write its electronic configuration and state the number of electrons it can lose to have a stable octet.
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Q51
short answer
1 mark
The atomic number of chlorine is 17. Write its electronic configuration. Name the nearest noble gas whose octet chlorine will attain after gaining one electron.
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Q52
short answer
2 marks
Show the formation of MgO by the transfer of electrons. The atomic numbers of magnesium and oxygen are 12 and 8 respectively.
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Q53
short answer
2 marks
Write the symbols and names of the anion and the cation present in the aqueous solution of the following compounds : (I) Sodium chloride (II) Potassium nitrate
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Besides heart, the human circulatory system consists of a network of closed branching blood vessels and the blood that circulates continuously in all parts of the human body. The human heart is a muscular organ which is as big as our fist. It has four chambers two upper chambers called atria and two lower chambers called ventricles. The right side of the human heart is separated from the left side by a dividing wall, which is known as septum.
Q54
short answer
1 mark
Name the smallest blood vessel and state its role in the circulation of blood.
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Q55
short answer
1 mark
Write the importance of platelets in the human blood.
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Q56
short answer
2 marks
Write in tabular form, two differences between an artery and a vein.
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Q57
short answer
2 marks
Why is blood circulation in the human heart called double circulation ? Explain.
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