(ENGLISH VERSION)
(Bifurcated Syllabus)
(For Regular and External Candidates)
Time : 3 Hours 15 Minutes Full Marks : 90 (for Regular Candidates)
(First fifteen minutes for : 100 (for External Candidates)
reading the question paper)
Group 'A' is compulsory. Answer ten questions from Groups 'B', 'C' and 'D' taking at least two from Group 'B' and at least three from each of the Groups 'C' and 'D' Besides this only the External Candidates will answer Group 'E'.
Figures in the margin indicate full marks for each question.
Group 'A'
1. Give very short answers to any ten of the following questions: 1 x 10 =10
1.1 The atom of an element has 2 electrons in the K shell, 8 electrons in the L shell and 7 electrons in the M shell. What is its atomic number ?
1.2 What is the value of standard temperature in Kelvin scale ?
1.3 What is the number of molecules in l.8 g water ? (H=1, O=16)
1.4 What is the SI unit of heat ?
1.5 Which colour of light suffers minimum deviation in the spectrum of white light ?
1.6 Write the relation between the size of the object and the size of the image when the object is placed at a distance of 2f before a convex lens of focal length f.
1.7 Which physical quantity is measured by kilowatt-hour ?
1.8 Name the upper thick pin of a three-pin plug top.
1.9 Write the name of the inert gas present in the first period of long periodic table.
1.10 Give an example of a biomolecule.
1.11 What is fuming nitric acid ?
1.12 In which solvent does the precipitate formed by adding AgNO3 solution to dilute hydrochloric acid dissolve ?
1.13 Write one use of vinegar.
Group 'B'
2.1 Write one similarity and one dissimilarity between the structure of solar system and that of atom. 2
2.2 What is mass number ? Can atoms of the same element having different mass numbers exist ? Explain with example. Whether their chemical properties are same or different ? Answer with reason. 1+2+1
2.3 When a balloon is inflated the volume increases with increase of pressure. Does it contradict Boyle's law ? Explain. 2
3.1 Write the number of electrons in[tex]{{_{19}^{40}K}}[/tex].Write the electronic arrangement of the atom having this number of electrons 2
3.2 Express Boyle's law in the mathematical form. Mention what the symbols used indicate. 2+1
3.3 The volume of a gas at 760 mmHg pressure and 0°C temperature is 300 cm3. What will be the volume of the. gas at 546°C temperature at the same pressure ? 3
4.1 State Charles' law related to gas. From this establish the definition of absolute zero of temperature. 2+2
4.2 What is an ion ? In the atom and an ion of an element which particle present in them differs in number ? 2
4.3 How many gram of sulphuric acid is required to neutralise 40g of sodium hydroxide completely ? ( S=32, Na=23, O=16, H=l ) 2
5.1 State Avogadro's law. If there are 6.022 x 1023 molecules present in V litre of nitrogen gas at STP, how many molecules are present in 2V litre of sulphur dioxide gas at STP ? 2+2
5.2 Define atomic mass of an element in the scale of C-12. 2
5.3 If the volume occupied by 22g of CO2 at STP is 11.2 litre, calculate the molecular mass of CO2. 2
Group C
6.1.1 Write the principle of calorimetry mentioning the conditions.
6.1.2 Define specific heat. 2+2
6.2 What are the two common scales for measuring temperature ? 2
6.3 Between 0°C and 0°F which indicates higher temperature ? Answer with reason. 2
7.1 Write the SI units of temperature and water equivalent. 2
7.2 What is the upper fixed point of a thermometer ? 2
7.3.1 Mention two differences between real image and virtual image.
7.3.2 What is the linear magnification of an image ? 2+2
8.1 What are called convex lens and concave lens ? What is the optical centre of a lens ? 2+2
8.2 Define focus of a convex lens. 2
8.3 What are pure spectrum and impure spectrum ? 2
9.1.1 When do the current in a conductor and the potential difference between the two ends of a conductor become proportional to each other ?
9.1.2 What is the electromotive force of a cell ? 2+2
9.2 What is the resistance of a 200V-40W bulb ? 2
9.3 How can the strength of an electromagnet be increased ? 2
10.1 How are a voltmeter and an ammeter connected in a circuit ? What does a voltmeter measure ? 2+1
10.2 What is electric fuse wire ? Mention one characteristic of it. 2+1
10.3 Find out the equivalent resistance of two resistances 4 ohm and 12 ohm connected in parallel combination. 2
11.1 What is thermionic emission ? Name an instrument made on the basis of this principle. 2+1
11.2 Mention two properties of X-rays. 2
11.3.1 Among α, ß,[tex]\gamma[/tex]-rays which one has the highest penetrating power ?
11.3.2 What is called nuclear fission ? 1+2
Group 'D'
12.1 By which types of chemical bonds chlorine combines separately with sodium and hydrogen to form sodium chloride and hydrogen chloride? Show by drawing electron-dot structure in both the cases. 1+1+1+1
12.2 Give explanation in terms of electronic theory for simultaneous occurrence of oxidation and reduc tion with the help of the following example : Cu2+ + Zn = Zn2+ + Cu 2
12.3 Write the modified form of Mendeleef 's periodic law. 2
13.1 What are used as cathode, anode, and electrolyte in the preparation of pure copper from impure copper rod ? 3
13.2 Arrange the following elements in order of decreasing atomic size:
O, C, F, Li 2
13.3 Which one is electrolyte between mercury and acidified water ? Why ? 3
14.1 Select the required reagents from the following for the preparation of hydrogen chloride in the laboratory:
(i) concentrated HNO3
(ii) concentrated H2SO4
(iii) AgCl
(iv) AlCl3
(v) NaCl
Give balanced equation of the reaction. How would you collect the gas ? How is hydrochloric acid prepared from hydrogen chloride ? . (Description of experimental procedure is not required) 4
14.2 Mention one harmful effect of the presence of SO2 in air. Write the name of an air-pollutant gas evolved from goldsmith's workshop. 2
14.3 Write two sources of SO2 in air. 2
15.1 Copy the following table in your answer script and complete the table.
| Name of the substance | Solubility in water | Organic or inorganic | One use |
| Slaked lime | |||
| Ammonium sulphate | Soluble | ||
| Naphthalene |
½ x 8 = 4
15.2 Write two differences between organic and inorganic compounds. 2
15.3 What chemical reaction takes place when methane is burnt in air ? What is the importance of this reaction ? 1+1
16.1 Write the general formula of alkyne. What functional group is present in aldehyde ? 1+1
16.2 What is the monomer of polyethylene ? Write two hazards of using polyethylene materials ? 1+2
16.3 There are three acids (HCl, H2SO4, HNO3) in three separate bottles. How would you identify which one is nitric acid with the help of copper turnings ? Give balanced equation. 3
17.1.1 Write the names of one ore of each of zinc and aluminium.
17.1.2 What are the ingredients of stainless steel ? Mention one use of it. 2+2
17.2 How will you prepare nitric acid from chilli saltpetre ? Give balanced equation of the reaction. 2
17.3 How would you convert ? HC = CH → CH3CH3 2
[ For External Candidates only ]
Group 'E'
18. Answer any five questions: 2 x 5
18.1 How does the temperature of a gas depend on the motion of gas molecules ?
18.2 What are the anode and cathode to be used to coat an iron spoon with copper ?
18.3 Define resistivity with its unit.
18.4 Write two important differences between ß and[tex]\gamma[/tex]-rays.
18.5 How many gtam of oxygen will be obtained by heating 20.2 g potassium nitrate ? (Assume the reaction is complete)
[K = 39, N = 14, O = 16]
18.6 Write one use of each of H2SO4 and HNO3.
18.7 Explain 'will-o-the-wisp' produced in marshy land.
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