Madhyamik 2025Physical Science Question Paper Pdf

A’ category

1. Multiple choice questions. Four answer options are given below each question. Write the correct one: 1 x 15

1.1 Which of the following gases does not contribute to ozone depletion in the ozone layer? (a) NO (b) NO2 (c) CFC (d) CO2

1.2 What is the value of PV at STP for an ideal gas of 11.2 liters? (a) 2 RT (b) RT (c) 0.5 RT (d) 11.2 RT

1.3 According to the chemical equation below, CH4+2O2→CO2+2H2O, what volume of O2 is required at STP to burn 10 moles of CH4? (a) 448 L (b) 224 L (c) 44.8 L (d) 22.4 L

1.4 Which of the following materials has the highest thermal conductivity? (a) Silver (b) Diamond (c) Copper (d) Aluminum

1.5 If a red and a violet light ray are incident from air at the same angle on the surface of a prism and produce angles of refraction r and v respectively, which of the following is correct? (a) r=v (b) r=1v (c) r>v (d) r<v

1.6 A point light source is placed at the centre of curvature of a concave mirror. The angle of refraction between the rays incident on the mirror and those reflected from the mirror from this source is (a) 0° (b) 180° (c) 90° (d) 360°

1.7 Coulomb’s law of electric charge is applicable when two charges are (a) one point, one spherical (b) both spherical (c) one point, the other extended (d) both point

1.8 The properties of fuse wire are (a) high resistance, high melting point (b) low resistance, low melting point (c) low heat, high melting point (d) high resistance, low melting point

1.9 An α-particle contains (a) one proton, one neutron (b) one proton (c) two protons, two neutrons (d) one electron

1.10 Which of the following is not a periodic law of elements? (a) Density (b) Melting point (c) Boiling point (d) Radioactivity

1.11 Which of the following compounds does not have any molecule? (a) Hydrogen chloride (b) Calcium oxide (c) Methane (d) Ammonia

1.12 Which of the following statements is correct regarding the electrolysis of CuSO4 solution using Cu electrode? (a) The mass of cathode decreases (b) The mass of anode increases (c) The concentration of CuSO4 in the solution decreases (d) The concentration of CuSO4 in the solution remains unchanged

1.13 What colour is produced when H2S gas is passed through an alkaline aqueous solution of sodium nitroprusside? (a) Purple (b) Orange (c) Dark blue (d) Green

1.14 The formula of iron ore red hematite is (a) FeO (b) Fe2O3 (c) Fe2O4 (d) FeCO3

1.15 Which of the following compounds reacts with aqueous NaHCO3 to produce CO2? (a) CH3CH2OH (b) CH3CHO (c) CH3COCH3 (d) CH3COOH

 ‘B’ category

2. Answer the following questions (note the optional questions):

2.1 Which fuel gas is extracted from coal beds?

Or

Name any gas present in the air, the increase in which causes global warming.

2.2 Name an energy source that can be used for sustainable growth and development.

2.3 Write the following statement as true or false: The velocities of molecules in a gas kept in a closed container at a certain temperature and pressure are equal.

2.4 What is the nature of the V vs. T diagram according to Charles’s law?

2.5 Write the following statement as true or false: Among copper, invar and iron, the coefficient of linear expansion of iron is the lowest.

Or

What is the unit of coefficient of volumetric expansion?

2.6 What is meant by the pole of a spherical mirror?

2.7 Write one use of X-rays.

2.8 Name a device where electrical energy is converted into mechanical energy.

2.9 What are the two other wires in a household circuit other than the live wire?

2.10 What type of nuclear reaction is used to produce energy in a nuclear reactor?

Or

Give an example of a naturally occurring radioactive element.

2.11 Match the left column with the right column: 1 x 4

Left Column Right Column 2.11.1 A post-uranium element (a) Klypton 2.11.2 A noble element (b) Neptunium 2.11.3 It is prepared by carbon reduction of the oxide of the metal (c) Copper 2.11.4 A metal alloy in which the percentage of one metal is greater than the percentage of the other metal (d) Zinc

2.12 Which of chloroform and sodium chloride does not dissolve in water?

2.13 Name a metal that is extracted by electrolysis.

Or

What is the anode in the electroplating of silver on a brass spoon?

2.14 What energy causes chemical reactions during electrolysis?

2.15 With the help of suitable litmus paper, show that aqueous solution of ammonia is alkaline in nature.

Or

Fill in the blanks: NaOH+H2S→ —— +H2O

2.16 Write one use of urea.

2.17 Write the structural formula of propanone.

Or

Bhola was the first to prepare an organic compound from an inorganic compound in the laboratory. What is the organic compound?

2.18 Give an example of a biodegradable natural polymer.

‘C’ category

3. Answer the following questions (note the optional questions): 2×9

3.1 In which of the layers of the atmosphere is the pressure the highest? Write the reason. 20

3.2 Determine the ratio of the volumes occupied by 32g of O2 and 44g of CO2 gas at a temperature of 27°C and a pressure of 700 mmHg.

Or

A certain mass of gas occupies a volume of 520 cm3 at -13°C. When the gas is heated while keeping the pressure unchanged, the volume of the gas increases to 700 cm3. What is the final temperature of the gas in degrees Celsius? 2

3.3 Mention two properties of the image formed by a simple camera.

Or

Where will the image formed by a concave mirror of an infinitely large object be formed in front of the mirror? Mention one property of the image. 1+1

3.4 State one similarity and one difference between electromotive force and potential difference. 1+1

3.5 Give an example of an ionic compound to show that its ions do not obey the octet rule. 2

Or

Explain why the melting point of sodium chloride is much higher than the melting point of glucose. 2

3.6 Show that F forms ionic bonds with Na, but forms covalent bonds with H. (The atomic numbers of H, F and Na are 1, 9 and 11 respectively) 2

3.7 Write the balanced chemical equation of what happens when nitrogen gas is passed over calcium carbide heated to 100°C. 2

3.8 Write the balanced chemical equation for the production of metallic iron from ferric oxide by the thermite method. Mention one application of this method.

Or

Write the balanced chemical equation for the chemical reaction that occurs when a piece of metallic iron is added to an aqueous solution of CuSO4. What can be learned from this reaction about the relative positions of Cu and Fe in the activity class of metals? 2

3.9 Select members of a homogeneous class from the following compounds and arrange them in ascending order of molecular weight: CH3COOH, CH3CH2OH, CH3OCH3, CH3OH, C2H4, C2H6, CH3CH2CH2OH, C3H4 2

Or

Write with an example what is meant by functional group.

‘D’ category

 4. Answer the following questions (note the optional questions):

4.1 State Avogadro’s formula. At a given temperature and pressure, the molar volume (v/N) of real gases is approximately equal and its limiting value at STP is 22.4 L mol-1. How can Avogadro’s formula be derived from this experimental data? 2+1

4.2 A and B react with each other to produce C according to the chemical equation below: 2A+B→2C A, B and C are the symbols of three gaseous substances respectively. The vapour density of A and B are 32 and 16 respectively. Determine the vapour density of C. 3

Or

According to the chemical equation below 2ZnS+3O2→2ZnO+2SO2, how many (i) grams of ZnO and (ii) moles of SO2 will be produced from 100 moles of ZnS? (Zn = 65.5, S = 32, O = 16)

4.3 Give an example of volume expansion of a liquid on application of heat.

The area of ​​a solid is A1 sqm at temperature T1 K and A2 sqm at temperature T2K. Write the mathematical form of the coefficient of expansion of the solid with units. 1+2

Or

Write down the three factors on which the transfer of heat through solids depends. 3

4.4 What is the dispersion of light? What will be the dispersion inside the glass after refraction of white light incident on a glass plate at an angle of 45°? 2+1

4.5 The principal cross-section of a prism is an equilateral triangle. If a ray incident at an angle of 30° on one of the prism’s reflecting surfaces emerges at an angle of 45° from the other reflecting surface, what is the angle of refraction? 3

Or

If the wavelength of light in air is 6000 Å, what will be the speed and wavelength of that light in a medium with refractive index of 1.5? 1+2

4.6 Two metal conductors A and B of equal length have resistivities of 1.6 x 10-8 Ωm and 3.2 x 10-8 Ωm respectively. The two conductors are connected separately to the same potential difference. What is the ratio of their cross-sections so that the current through each of them will be the same?

Or

Two 10 ohm resistors are connected in series and the resistor is connected in parallel with a 20 ohm resistor. Determine the equivalent resistance of the final resistor. 3

4.7 What is meant by power? A bulb is rated 220V — 100 W — what does this mean? 1+2

4.8 Radioactive rays are emitted from which part of the atom? Which of the radioactive rays has the highest penetrating power and ionizing power? 1+2

4.9 State the difference between the hydrogen atom and one atom of group 1 elements and two atoms of group 17 elements. 1+2

Or

Arrange as instructed:

(a) Arrange Na(11), K(19), Li(3), Rb(37) belonging to group 1 of the long periodic table in the descending order of atomic radius.

(b) In the long periodic table, S(16), O(8), Te (52), Se (34) belonging to group 16 are arranged in order of increasing electronegativity.

(c) In the descending order of reducing power, Ca(20), Be(4), Sr(38), Mg(12) belong to group 2 of the long periodic table.

(The atomic numbers of the elements are given in the first bracket next to the symbols of the elements) 1+1+1

4.10 On what basis are electrolysis classified as strong and weak electrolysis? Give an example of strong electrolysis. 2+1

4.11 Describe how nitric oxide is produced by oxidizing ammonia with oxygen from the air, mentioning the name of the catalyst and the conditions. Also write the balanced chemical equation of the reaction. 2 + 1

4.12 Two different organic compounds A and B have the same molecular formula, C2H6O. A reacts with metallic sodium to produce hydrogen gas but B does not react with metallic sodium. Write the structural formula of compounds A and B. Write the balanced chemical equation for the reaction of metallic sodium with A. 2+1

Or state the conditions for the reaction of hydrogen addition to ethylene. Write the balanced chemical equation for the reaction. State one use of CNG. 2+1

‘E’ category

(For external candidates only)

5. Answer the following questions (any four) 1×4

5.1 In which layer of the atmosphere are convection currents seen?

5.2 When two resistors are combined in which coefficient, the equivalent resistance is less than both resistors?

5.3 A certain mass of a gas occupies a volume of 150 cm3 at a certain temperature and 1 atmosphere of pressure. What volume will the gas occupy at that temperature and 1.5 atmosphere of pressure?

5.4 Which radioactive rays are composed of negatively charged particles?

5.5 Mention one use of ethylene.

6. Answer the following questions (any three): 2×3

6.1 Write the difference between semiconductor and superconductor based on the relationship between resistivity and temperature. 6.2 What is a diverging lens?

6.3 Write the balanced chemical equation of what happens when ammonium chloride is heated with dry lime.

6.4 Write what is meant by saturated hydrocarbon with an example.