Chemistry Sample Paper, Study notes of Chemistry

Download Chemistry Sample Paper and more Study notes Chemistry in PDF only on Docsity! Be. ny CBSEguide. com A Complete guide for CBSE students Sample Paper-03 Chemistry (Theory) Class - XI Time allowed: 3 hours Maximum Marks: 70 General Instructions: a) All the questions are compulsory. b) There are 26 questions in total. c) Questions 1 to 5 are very short answer type questions and carry one mark each. d) Questions 6 to 10 carry two marks each. e) Questions 11 to 22 carry three marks each. f) Questions 23is value based question carrying four marks. 8) Questions 24to 26 carry five marks each. h) There is no overall choice. However, an internal choice has been provided in one question of two marks, one question of three marks and all three questions in five marks each. You have to attempt only one of the choices in such questions. i) Use of calculators is not permitted. However, you may use log tables if necessary. 1. Draw the structure of (a) 2, 3-Dimethylpentane (b) 4-Phenylbut-1-ene 2. If a tank is full of water coming in and out ai the same rate, then what will happen to the level of water in a tank? 3. Express 32.392800 to four significant figures. 4, Write the correct symbol for the mucieus with: (i) Atomic number 56 and mass number 138 (ii) Atomic number 26 and mass number 55. 5. Why is Ga smaller in size fan Al? 6. The standard solution of NaOH cannot be prepared by weighing. Why? 7. Give reason: “Although gcometries of ammonia and water molecules are distorted tetrahedral, bond angie iz water is less than that of ammonia”. Or Why is benzene exira-urdinary stable though it contains three double bonds? 8. In the estimation of sulphur by Carius method, 0.468 g of an organic sulphur compound afforded 0.668 g of barium sulphate. Find out the percentage of sulphur in the given compound. 9. (a) Is it possible to achieve equilibrium between water and its vapour in an open vessel? (b) Explain your answer and say what happens eventually. 10. How does electronegativity vary i) down the group and ii) across the period? 11. (i) Which of the two is more stable H} or H; and why? (ii) All bonds in PCls are not equal. Explain. Material downloaded from http://myCBSEguide.com and http://onlineteachers.co.in Portal for CBSE Notes, Test Papers, Sample Papers, Tips and Tricks 12. 13. 14, 15. 16. 17. 18. 19, Be. ny CBSEguide. com A Complete guide for CBSE students (iii) Which of the two is more ionic - NaCl or Nal and why? Explain the following terms with an example each: (i) Open system (ii) Isolated system (iii) Closed system Draw the structure of the following IUPAC compounds: (a) 2, 8-Dimethyl-3, 6-decadiene (b) 4-Ethyl-2, 6-dimethyl-dec-4-ene (c) 1,3,5,7 Octatetraene (d) 4-Nitroso-N-dimethylbenzenamine (e) Benzene 1, 4-dicarboxylic acid (f) 1-Phenylpropanone (i) Calculate the percentage of C and H in 0.2475 g of an organic compound gave on combustion 0.4950 g of carbon dioxide and 0.2025 g of water. (ii) What will happen during Lassaigne's test for nitrogen if the compound also contains sulphur? If water vapour is assumed to be a perfect gas, molar enthalpy change for vapourisation of 1 mol of water at 1bar and 100°C is 41kJmol-. Calculate the internal energy change, when (i) 1 mol of water is vaporised at 1 bar pressure and 100°C (ii) 1 mol of water is converted into ice. Explain: (i) Boron is unable to form BF¢?- ion. (ii) [SiFe]*- is known whereas [S not known. (iii) Conc. HNOs can be steved in atuminium container. Identify the species undergoing oxidation and reduction in the reactions given below. (i) H2S (g) + Cl2 (g) > 2 HCI (gj + S (s) (ii) 3Fe304 (s) + 8 Al (s} > 9 Fe (s) + 4Al203 (s) (iii) 2 Na (s) + Hz (g) -> 2 NaH (s) What are the conclusions made by Rutherford w.r.t the structure of atom? Define the following terms: (i) Functional groups (ii) Homologous series Or Predict about the formation of M3* ion in solution and compare the electropositive character of the two metals given. The standard electrode potential values, E° for Al3*/Al are -1.66 V and that of TI3*/TI is +1.26 V. Material downloaded from http://myCBSEguide.com and http://onlineteachers.co.in Portal for CBSE Notes, Test Papers, Sample Papers, Tips and Tricks