Category – A
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 absorbs long wavelength infrared radiation emitted from the Earth’s surface? (a) N2 (b) O2 (c) CH4 (d) He
1.2 At STP 2.24 L occupies (a) 4.4g CO2 (b) 0.64g SO2 (c) 28g CO (d) 16g O2 (C=12, O=16, S=32)
1.3 How many molecules of CO2 will be produced if 1 mole of C reacts completely with 1 mole of O2? (a) 6.022 x 1023 (b) 1.806 x 1024 (c) 6.022 x 1022 (d) 6.022 x 1024
1.4 How many types of thermal expansion coefficients does a solid have? (a) One (b) Two (c) Three (d) Four
1.5 Which of the following has the longest wavelength? (a) X-rays (b) γ-rays (c) Infrared rays (d) Ultraviolet rays
1.6 In the case of refraction, if the angle of incidence and angle of refraction are 45° and 30° respectively, then the value of angular deviation will be (a) 75° (b) 15° (c) 7.5° (d) 37.5°
1.7 If the potential difference across a conductor at constant temperature is V and the current through the conductor is I, which of the following is true? (a) V∝I (b) V∝I2 (c) V∝I−1 (d) V∝I−2
1.8 The relationship between electromotive force (V), work (W) and charge (Q) is (a) Q=WV (b) Q=VW (c) Q=VW2 (d) Q=WV
1.9 The emission of β-particles from a radioactive atom results in (a) an increase in the mass number of the resulting atom (b) an increase in the atomic number (c) a decrease in the mass number (d) an decrease in the atomic number
1.10 In which group of the long periodic table are the halogen elements located? (a) Group 1 (b) Group 16 (c) Group 17 (d) Group 2
1.11 The solid state of which of the following compounds is composed of ions? (a) Sodium chloride (b) Hydrogen chloride (c) Naphthalene (d) Glucose
1.12 Which of the following has the highest electrical conductivity? (a) Pure water (b) Aqueous sugar solution (c) Liquid hydrogen chloride (d) Aqueous acetic acid solution
1.13 Which of the following compounds is produced by the first step of nitrogen bonding when electricity is applied? (a) NO (b) NO2 (c) N2O5 (d) HNO3
1.14 Which of the following is the formula for the aluminium ore bauxite? (a) AI2O3 (b) AI2O3 . H2O (c) AL2O3 . 2H2O (d) AIF3 . 3NaF
1.15 Which of the following is an alkyl group containing two carbon atoms? (a) Methyl (b) Ethyl (c) Propyl (d) Isopropyl
Category – B
2. Answer the following questions (note the optional questions):
2.1 Write the unit of heating value of fuel or, does the temperature increase or decrease with increasing height in the stratosphere?
2.2 The ozone layer prevents which rays from the sun from reaching the earth’s surface?
2.3 Write whether the following statement is true or false: The volume of gas molecules is calculated using Avogadro’s formula.
2.4 How many grams of N2 gas at STP have a volume and pressure of 224 liter-atmosphere? [N = 14]
2.5 Write the following statement as true or false: During the transfer of heat through a material, the material’s constituent particles change position.
Or, if the resistance and cross-sectional area of a conductor remain unchanged, what is the relationship between the thermal resistance and thermal conductivity of that conductor?
2.6 What is the angle of refraction when a light ray passes through the center of curvature of a concave mirror?
2.7 How many rectangular faces does a prism have?
2.8 Give an example of a semiconductor.
2.9 A thin wire and a thick wire of the same conductor are of equal length. If they are placed at the same potential difference, which one will carry more current?
2.10 Mention one misuse of nuclear fission reaction.
Or, what formula explains the enormous amount of energy released in nuclear fusion?
2.11 Match the left column with the right column: 1 x 4 = 4
Left Column Right Column 2.11.1 Protected from attack by water vapor by oxide layer (a) Cu 2.11.2 The metal with the least redox properties in group 1 of the long periodic table (b) Be 2.11.3 The metal slowly tarnishes when exposed to open air (c) Al 2.11.4 The element with the smallest atomic radius in group 2 of the long periodic table (d) Li
2.12 Draw the Lewis dot diagram of N2 molecule. (Atomic number of N is 7)
2.13 What type of electric current is used in electrolysis?
Or, write the cathode reaction in the electrolysis of acidified water using a platinum electrode.
2.14 What is used as an electrolytic agent to electroplate gold on brass?
2.15 What color is produced by the reaction of ammonia with Nessler’s reagent?
2.16 Write the symbol for the precipitate formed when H2S gas is passed through an aqueous solution of silver nitrate.
Or, write the name of the compound that is produced by the reaction of magnesium metal with nitrogen at high temperature.
2.17 What is the value of the H — C — H bond angle in the methane molecule?
Or, write the IUPAC name of CH3CH2COOH.
2.18 What is the industrial source of CNG?
Section – C
3. Answer the following questions (optional questions are noted) 2×9
3.1 What is the concept of sustainable development?
3.2 1 gram of a gas occupies a volume of 410 mL at 7°C and 2 atmospheres pressure. Determine the molar mass of the gas. (R = 0.082 liter.atmosphere.mol -1.K-1)
Or, at STP, a certain mass of gas occupies a volume of 273 cm3. At what pressure and temperature of 27°C will that gas occupy a volume of 300 cm3?
3.3 What is the refractive index of a medium?
Or, what type of vision defect is corrected by convex lenses?
3.4 Two resistors r1 and r2 are connected separately across the same potential difference and it is found that the current through r1 is six times the current through r2. Determine the ratio of r1 to r2.
3.5 How does Koschel explain the formation of ionic bonds?
Or, liquid hydrogen chloride is not capable of conducting electricity, but molten sodium chloride is capable of conducting electricity. —Explain.
3.6 Differentiate between sodium chloride and naphthalene with the help of two physical properties.
3.7 Two aqueous solutions, one is ferric chloride and the other is aluminum chloride. How will you identify the ferric chloride solution using an aqueous solution of ammonia? Answer with a balanced chemical equation.
3.8 Why can zinc blende be called both a mineral and an ore of zinc?
Or, mention two ways to prevent iron from rusting.
3.9 Write the balanced chemical equation for what happens when methane is burned in oxygen.
Or, mention one use each of acetic acid and ethyl alcohol.
Category – 1
4. Answer the following questions (note the optional questions):
4.1 What is meant by molar volume of a gas? Mention two reasons for deviation of real gases from ideal gas behavior. 1+2
4.2 How many grams of Al are required to prepare 558 g of Fe by reducing Fe2O3 with Al at high temperature? How many moles of Fe2O3 are required in the reaction? (Fe = 55.8, Al = 27, O = 16) 2 + 1
Or, 32.1 g of ammonium chloride was heated with calcium hydroxide to produce 10.2 g of NH3, 33.3 g of CaCl2 and 10.8 g of H2O. How many grams of calcium hydroxide participated in the reaction? How many moles of NH3 were produced in this reaction and how many liters of NH3 at STP were produced? (N = 14, H = 1) 1+2
4.3 What is constant in the definition of the coefficient of volumetric expansion of a gas? Write the name of a non-metal which is a good conductor of heat. 2+1
Or, what does ‘coefficient of linear expansion of copper is 17×10-6 /°C’ mean? Why is this value the same on the Kelvin scale? 2+1
4.4 What type of mirror do dentists use? Why does refraction of light rays not cause deflection in the glass? 1+2
4.5 An object placed 20 cm away from a convex lens does not form an image on either side of the lens. What is the focal length of the lens? If the refractive index of glass with respect to air is 1.5, what is the refractive index of air with respect to glass? 2+1
Or, an object is 5 cm long. It is placed in front of a convex lens at a distance of 2 cm and an image of length 10 cm is obtained. What is the linear transformation and the distance of reflection? 1+2
4.6 Briefly write the basic technique of hydroelectric power generation. 3
4.7 When an electric lamp is connected to a 220V mains, a current of 1A occurs. How much current will there be if the same lamp is connected to a 110V mains?
Or, determine the ratio of the resistance of two lamps 220V – 60W and 110V – 60W.
4.8 Explain why the emission of α-particles from a radioactive element produces new elements but the emission of γ-rays does not produce new elements. 2+1
4.9 Write the Dobereiner’s triple formula. Arrange Cl, Br, I, F in the order of their increasing oxidation number. 2+1
Or, what is the important conclusion of Mozl’s experiment? What is the significance of this conclusion in the context of the periodic table? 2+1
4.10 Write two differences between the conduction of electricity through a metal wire and the conduction of electricity through electrolysis during electrolysis. In the electrolysis method, which electrode is used as an impure copper rod in the purification of copper metal? 2+1
4.11 Write the names of the chemicals used in the industrial production of urea and the chemical equations of the reactions. 3
4.12 (A) and (B) are two unsaturated hydrocarbons containing 2 carbon atoms each. On reaction with bromine, 1 molecule of bromine is added per molecule in (A) and 2 molecules of bromine are added per molecule in (B). Write the structural symbols of (A) and (B). Write the balanced chemical equation for the reaction of bromine with (B). 2+1
Or, write the balanced chemical equation for the reaction of acetic acid with sodium hydroxide. Which of jute and polythene is more environmentally friendly for use in packaging and why? 1+2
