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Name of the School : National Institute of Open Schooling
Name of the Exam : Senior Secondary Chemistry
Document type :Sample Question paper
Website : nios.ac.in

Download Model/Sample Question Papers : https://www.pdfquestion.in/uploads/nios.ac.in/5351-sqp313e.pdf

Chemistry Sample Question paper :

Time : 3 hrs.
Maximum Marks : 80

Related : National Institute of Open Schooling Senior Secondary English Sample Question Paper : www.pdfquestion.in/5347.html

Note :
(i) All question in Section A are compulsory.
(ii) Attempt only one out of two options in section B, i.e., attempt either Part I or Part II or Part III in Section B.
(iii) Marks for each question is indicated against it.
(iv) Use log tables if necessary.

Section A
1. What is the molar mass of NH3? (1)
2. A Sample of nitrogen gas consists of 4.63 × 1022 nitrogen atoms. How may moles of N atoms are there? (1)

3. What is the lowest possible temperature in Kelvin units? (1)
4. Derive SI units for
(i) Force (ii) Pressure (2)
5. Explain the geometry of the following:
(i) NH3 (ii) B F3 (2)

6. A sample of nitrogen gas weighing 9.3 g at a pressure of 0.99 atm a accoutres a volume of 12.4 litres at 55K temperature. What do you expect its volume to be when the temperature is 220 k? Assume that pressure stays constant. (2)

7. What is the relationship between the standard free energy change and the equilibrium constant of the reaction? (2)

8. Calulate enthalpy for the following reaction :
2H2 + O2 (g) → 2H2O(g)
Given Bond energy of H-H bond = 436 KJ mol–1
Bond energy of O – H bond = 423 KJ mol–1
Bond energy of O = O bond 496.4 KJ mol–1 (2)

9. Arrange the following oxides in the increasing order of acidic property. Justify your answer. Al2O3, CO2, SO2, B2O3 (2)
10. Draw the structure of the following:
(i) H3 PO3 (ii) P4 O10
(iii) H2S2O3 (iv) ClO2 (4)

11. Explain the following giving suitable reasons
(i) BF3 is weaker lewis acid as compared to BCl3
(ii) CCl4 does not hydrolyse but SCl4 does.
(iii) N2 is inert at room temperature.
(iv) SF4 is known but SCl6 is not. (4)

12. (i) What is le Chatelier’s principle?
(ii) For the following reaction:
C2H4 (g) + I2 (g) → C2H4I2(g) the rate of recation is rate = K [C2H4 (g)/ I2 (g)]3/2
(a) What is the order of the reaction with respect to each reactant?
(b) What is the overall order of the reaction?
(c) What is the unit of K, if the concentrations are measured in mol dm–3 sec–1? (4)

13. A cell is set up between Cr and Cu electrodes
(a) Cr(s)| Cr3+ (aq) || Cu2+ (aq) | Cu(s)
If the two lalf cells work under standard conditions, calculate the e.m.f. of the cell. E° Cr3+| Cr = – 0.74 V ; E° Cu2+ | Cu = + 0.34 V

(b) Calculate KP for the reaction COCl2 CO + Cl2 in atom and Nm–2, The equilibrium partial pressure of COCl2, CO and Cl2 are 0.20, 0.16 and 0.26 atm. respectively. (1 atm = 101300 Nm–2) (4)

14. (a) Write down ideal gas equation.
(b) Give three different values of R in the ideal gas equation. (4)

15. (a) Write the IUPAC names of the following organic compoumds
(b) Define the following (any two only)
(i) Electrophiles (ii) Nucleophiles
(iii) Catenation (iv) Isomerism (4)

16. (a) What is electrovalent bond? Explain the term lattice energy as applied to ionic crystal How is enthalpy of formation of NaCl calculated, using Born Habeis cycle?
(b) Why is sigma bond stronger than π – bond? (4)

17. (a) 0.0663g of an organic compound on combustion geve 0.621 g of CO2 and 0.0381g of H2O.
(b) What is the ratio of the mass of orygen that combines with 1.0g Carbon in carbon monoxide and carbon dioxide? (4)

18. (a) Write de Broglic expression.
(b) Write down Balmer formula and explain the terms imrowed, what is the wavelength of the light emitted when the electron in a hydrogen atom jumps from N2 = 4 to N1 = 1 levels? (Rydberg Constant R = 109677 cm–1) (6)

Section – B :
Part-I : (Environmental Chemistry)
1. (a) Define any Two of the following terms
(i) Pollutant (ii) Biosphere
(iii) Eutrophication (iv) Biological oxygen Demand (BOD) (2)
(b) List four effects of acid rain (2)

2. Describe with the help of diagram the three stages of treatment of waste water (6)
3. How does carbon get into the environment from dead organic mater. (1)
4. Show diagrammatically how heavy metals enter into the echo system. (2)