Central Board of Secondary Education (CBSE)
Sample Paper – 2012
Class – XII
Subject – Chemistry
- What causes Brownian movement in a colloidal solution?
- Write the IUPAC name of the following organic compound. CH3-O-CH2-CH(OH)-CH2-CH3
- Arrange the following compounds in an increasing order of acidic strengths: CH3CH2CH(Br)COOH, CH3CH(Br)CH2COOH, (CH3)2CHCOOH, CH3CH2CH2COOH.
- Write chemical equation when PtF6 and xenon are mixed together.
- What is the use of SO2 formed during the roasting of sulphide ores?
- Mention a large scale use of the phenomenon called reverse osmosis?
- Write an example of a neutral molecule which is isoelectronic with ClO–.
- Write structural formula of 2,3-dichloropentane. State whether it is optically active or not.
- State Raoult’s law for solutions of two volatile liquids. Taking suitable examples explain the meaning of positive and negative deviation from Raoult’s law.
10. Calculate the amount of KCl which must be added to 100g of water so that water freezes at -2.0oC.Assume that KCl undergoes complete dissociation.
11. Distinguish between order and molecularity of a reaction. When could order and molecularity of a reaction be the same?
12. Outline the principles of the following:
(i) Zone refining
(ii) Paper chromatography.
13. State the difference between Schottky and Frenkel defects. Which of the two changes the density of the solid?
14. Analysis shows that nickel oxide has formula Ni0.96O1.00. What fractions of nickel exist as Ni2+ and Ni3+ ions?
15. What happens when D-Glucose is treated with the following reagents?
(ii) Bromine water.
16. Answer the following:
(i) What type of linkage is responsible for the primary structure of proteins?
(ii) What are any two good sources of vitamin ‘A’?
17. Explain the difference between:
(a) Aniline and Ethylamine
(b) dimethylamine and Methylamine
18. Account for the following:
(i) Aniline does not undergo friedel-crafts reaction.
(ii) Methylamine in water reacts with ferric chloride to precipitate hydrated ferric oxide.
19. Define the following with a suitable example.
(a) Coupling reaction.
(b) Reimer-Tiemann reaction.
20. (a) Why aryl halides are extremely less reactive towards nucleophilic substitution reaction?
(b) In the following pairs of halogens compounds, which compound undergoes faster SN1 reaction?
21. The following data were obtained during the first order thermal decomposition of SO2Cl2at constant volume.
22. Write short notes on the following:Calculate the rate of the reaction when total pressure is 0.65 atm.
(a) Froth Floatation process.
(c) Zeta potential.
23. Complete the following chemical equations:
(ii) HgCl2 +PH3→
24. Account for the following:
(i) NH3 is stronger base than PH3.
(ii) The electron gain enthalpy with negative sign for oxygen is less than that of sulphur.
(iii) H3PO2 and H3PO3 act as good reducing agent while H3PO4 does not.
25. Indicate the type of isomerism exhibited by the following complexes and draw the structures for these isomers:
(i) [Co (en)2Cl2]
26. (a) Differentiate between the thermoplastic and thermosetting polymers.
(b) What are biodegradable polymers? Give two examples.
27. State the function along with one example each of:
28. (a) State two advantages of H2-O2 fuel cell over ordinary cell.
(b) A copper-silver cell is set up. The copper ion concentration in it is 0.10M. The concentration of silver ion is not known. The cell potential measured is 0.422V. Determine the concentration of silver ion the cell.
(Given: Eo Cu2+/Cu=+0.34V and EoAg+/Ag=+0.80V)
29. (a) Write the steps involved in the preparation of:
(i) K2Cr2O7 from Na2CrO4.
(ii) KMnO4 from K2MnO4.
(b) What is meant lanthanoid contraction? What effect does it have on the chemistry of the elements which follow lanthanoids?
30. (a)Define your view about following conversions in more than two steps? (i) Propanone to Propene (ii) Benzoic acid to Benzaldehyde.
(b) An organic compound ‘A’ contains 69.77% carbon, 11.63% hydrogen and the rest is oxygen. The molecular mass of ‘A’ is 86. It does not reduce Tollen’s reagent but forms an addition compound with sodium hydrogen sulphite. ‘A’ gives a positive iodoform test. On vigorous oxidation ‘A’ gives ethanoic and propanoic acids. Deduce the possible structure of molecule of ‘A’.
Sample Paper / Model Test Paper CBSE 12th 2012
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Subject – General English
Directions (1-10): In the following passage there are blanks, each of which has been numbered. These numbers are printed below the passage and against each four words are suggested, one of which fits the blank appropriately. Find out the appropriate word.
A two party (1) is must for a democratic country like (2) to achieve national objectives (3) as removal (4) unemployment,
MODEL PRACTICE SET
Subject- General English
Combined Graduate level Examination SSC 2011
Directions (1-10): A passage is given below in which blanks have been numbered. Four alternative choices are given below against each number. In the context of the whole passage, select the best word in each case to fit each of the blanks to complete the passage correctly and meaningfully.
During the World War I penicillin was (1) on six patients.
BANK PROBATIONARY OFFICER (BANK PO)
1. Which country will introduce entrepreneur visa to encourage foreign nationals from India and elsewhere to catalyze the country’s economic recovery?
(a) US (b) Britain
(c) France (d) Denmark
(e) None of these
2. Name the state whose chief minister has said that the Armed Forces Special Powers Act can be withdrawn from some areas with a rider that the Army can step in again if the situation so warrants.
Bank Probationary Officer ( Bank PO)
1. Name the Karnataka minister who resigned in the wake of the Lokayukta police filing a first information report against him on irregularities related to allotment of land through the Karnataka Industrial Area Development Board (KIADB).
(a) Katta Subramanya Naidu (b) N Santosh Hegde
(c) Jagmohan Reddy (d) Roshan Baig
(e) None of these
NABARD Bank PO
1. Which of the following is rated the poorest region of the world?
(a) The Middle East (b) Asia
(c) Sub-Saharan Africa (d) Latin America
(e) None of these
2. Which of the following terms is not used in the world of economics/finance?
(a) Sinking Fund (b) Third World
(c) Open Door Policy (d) Devaluation
(e) Privilege Motion