(Download) NIOS Question Paper Of Chemistry Senior Secondary

Time : 3 hrs.

Maximum Marks : 80

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 × 10 ²² 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) P₄O₁₀
(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:

C₂ H₄ (g) + I₂ (g) → C₂ H₄ I₂ (g)
the rate of recation is rate = K [C₂ H₄ (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 K_p 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 :

Click Here To Download Question Paper

<< Go Back To Main Page