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ISC Class 12 Chemistry Solved Question Paper 2009

Short Answer Type

31.
How will you bring about the following conversions :

(i) Acetaldehyde to acetamide.

(ii) Phenol to benzoic acid

(iii) Glucose to saccharic acid.

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32. Give the names of the following reactions:

straight i right parenthesis space straight C subscript 2 straight H subscript 5 Br space plus straight C subscript 2 straight H subscript 5 ONa space rightwards arrow straight C subscript 2 straight H subscript 5 OC subscript 2 straight H subscript 5 space plus NaBr ii right parenthesis space CH subscript 3 CHO space plus CH subscript 3 COCH subscript 3 space rightwards arrow with OH to the power of minus on top space CH subscript 3 CH left parenthesis OH right parenthesis CH subscript 2 COCH subscript 3

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33.

How will you distinguish between the following pairs of compounds ? (Give one good chemical test.)

(i) Ethylamine and Acetamide
(ii) Oxalic acid and Acetic acid.

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34. An organic compound A with molecular formula C₂H₇N on reaction with nitrous acid gives a compound B. B on controlled oxidation gives a compound C. C reduces Tollen’s reagent to give silver mirror and D. B reacts with D in the presence of concentrated sulphuric acid to give a sweet smelling compound E. Identify A, B, C, D and E. Give the reaction of C with ammonia and name the product.

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35. Draw the isomers of a compound with the molecular formula C₄H₄O₄. Name the isomers.

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36.

What type of polymerisation takes place when a polyester is formed? Give one example of a polyester and name the monomers from which it is formed.

(ii) Give two examples of natural polymers.

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37.

Identify the products A, B, C and D.

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38.

Give balanced equations for the following reactions:

(i) Formic acid heated with Tollen’s reagent.

(ii) Phenol heated with chloroform and sodium hydroxide.

(iii) Acetaldehyde reacted with phenyl hydrazine.

(iv) Aniline treated with benzoyl chloride.

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Long Answer Type

39.

i) Write the mathematical expression for the first law of thermodynamics.

One mole of an ideal gas is expanded isothermally against a constant pressure of 3 atmospheres from 10 litres to 35 litres. Calculate the work done, change in internal energy and heat absorbed during the process.

(ii) Calculate the free energy change of the reaction:

C_(graphite)+O₂ (g) →CO₂(g) ΔH = - 300 kJ mol^-1 and AS = 3JK^-1 mol^-1 at 300 K.

Predict whether the reaction is spontaneous or not at 300 K.

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