SAMPLE PAPER - I (Unsolved)

CHEMISTRY - XI

Time allowed: 3 hrs.

M. M.: 70

General Instructions:

1. All questions are compulsory.
2. Marks for each question are indicated against it.
3. Question number 1 to 8 are very short answer questions carrying one mark each. Answer these in one word or about one sentence.
4. Question number 9 to 18 are short answer questions carrying 2 marks each. Answer these in about 30 words.
5. Question number 19 to 27 are also short answer questions carrying 3 marks each. Answer them in about 40 words.
6. Question number 28 to 30 are long answer questions carrying 5 marks each. Answer them in about 70 words.
7. Use log tables, if necessary. Use of calculator is not allowed.

1. Write the electronic configuration of <math>Cu^*</math> (<math>Z = 29</math>).
2. State modern periodic law.
3. Give one example of intensive property.

1. What would you observe when HCl gas is passed into the saturated solution of NaCl?
2. Calculate oxidation state of Mn in K₂MnO₄.
3. Draw the structure of C2H5+.
4. Which reactive intermediate is formed when the covalent bond in CH,-Li 1 under-goes hetrolytic cleavage?

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1. Predict the alkene as a major product obtained by the dehydrohalogenation of :

Br CH₃ | | | CH₃-CH₂—C—C—CH₃ CH, CH,

1. A sample of NaOH weighing 0.38 g is dissolved in water and solution 2 is made 50.0 mL in a volumetric flask. Calculate the molarity of the resulting solution. (Molar mass of NaOH = 40 g mol^-1)

Electromagnetic radiation of wavelength of 242 nm is just sufficient to ionise sodium atom. Calculate the ionization enthalpy of sodium in kJ/mol. 2

Draw the energy level diagram of molecular orbitals in N, molecule. 2

On the basis of kinetic theory of gases explain why 2

1. gases exert pressure.
2. the volume of fixed amount of gas at constant pressure increases with the rise in temperature.

A student forgot to add the reaction mixture to a flask at 27° C and 2

placed on the flame and heated it to 477° C. What fraction of air has been expelled out?

1. State Le Chatelier principle. Predict the direction of the reaction: 2 when noble gas is added to the reaction mixture at constant pressure.

Balance the following chemical equation in alkaline medium: 2

<math>I^- + MnO_4^- \rightarrow IO_3^- + MnO_3^-</math>

1. Contrast the action of heat on the following and explain your answer: 2
2. Na,CO, and CaCO,
3. Ca(NO₃), and NaNO₃
4. Write the chemical equations for the following reactions:
5. Markownikov's rule (b) Friedel-Crafts reaction 2

OR Explain the following technique of separation of organic compounds with suitable examples: 2

1. Chromatography (b) Differential extraction

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