How was the CBSE Chemistry exam 2016?
How much do you expect in CBSE Chemistry theory paper?
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- Synthetic detergents can be used even in acidic medium as they are the salts of strong acids and are not decomposed in acidic medium.
- Synthetic detergents have a stronger cleansing action than soaps.
- Synthetic detergents are more soluble in water than soaps.
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Electrochemistry – Long Answer Type Questions
- What is galvanic cell?Explain the working of a galvanic cell by taking the example of Zn/CuSO4 reaction.Explain in brief the function of the salt bridge?
- What is electrode potential?describe the orgin of electrode potential when a metal strip is placed in a solution of its own ions.In what respects electrode potential differs from standard electrode potential?
- What do you understand by battery?Describe the chemistry of lead storage battery during its discharging and recharging process highlighting all the materials that are involved?
- What is corrosion of metals?How is rusting of iron envisaged as setting of electrochemical cell?Explain.Can a coating of tin over iron surface prevent rusting?Comment.
- What is meant by electrolytic conduction?On what factors does it depend?How does it differ from metallic conduction?
- Derive the relationship between (1) Conductivity and molar conductivity and (2)Standard cell potential and equilibrium constant?
- How does emf of a cell vary with temperature?Explain in brief?
- State and explain Kohlrausch law?How can it help to calculate (1) limiting molar conductivity of weak electrolyte and (2)degree of dissociation of weak electrolyte.
- How do you account for the variation of molar conductivity of weak and strong electrolytes with concentration?
- Iron does not rust when a coating of zinc cover its surface cracks in galvanised iron pipes , but it rusts rapidly when a coating of tin done on its surface cracks.Explain.
- What is electrolysis?What role does electrode potential play while deciding the products of electrolysis?
- Write short note on (1)Hydrogen economy (2)Faradays-laws of electrolysis
Prepare for AISSCE (CBSE Class XII) Chemistry through selected Long ANswer Type Questions – Unit 1 – The Solid State
Chapterwise long answer type questions for AISSCE (CBSE Class XII) Chemistry
Unit 1 – The Solid State
- Describe the following
- Hexagonal close packing
- Cubic close packing
- Body centred cubic packing
- What are the seven types of crystal systems? Give their unit cell dimensions. Draw structures of different types of unit cells which are possible for cubic crystal system.
- What do you mean by stoichiometric point defects? Describe briefly the various types of stoichiometric point defects.
- Explain the following.
- Schottky defect
- Frenkel defect
- F – centres
- Explain the conduction behaviour of metals, semiconductors and insulators on the basis of band theory of solids. What is the effect of increase of temperature on electrical conductivity of metals, semiconductors and insulators.
- Explain the following with suitable examples
- Paramagnetic substances
- ferrimagnetic substances
- Ferromagnetic substances
MM : 25 TIME : 45 MIN.
1. Give IUPAC names of the following compounds:
(a) CH2=CH-CH – C=CH2
2. Write the structure of the following organic halogen compounds :
3. Explain the following reaction:
(a) Friedel craft alkylation reaction.
(b) Wurtz reaction
(c) Sandmeyer’s reaction
(d) Finkelstein reaction
4. Convert the following:
(a) Ethane to bromoethene
(b) But-1-ene to but-2-ene
(c) Propene to propyne
(d) Benzyl alcohol to 2-phenylethanoic acid
(e) Aniline to chlorobenzene
5. Explain Markownikoff’s rule with example.
6. Explain the following
(a) Vinyl chloride is hydrolysed more slowly than ethyl chloride
(b) The treatment of alkyl chloride with aqueous KOH leads to the formation of alcohols but in the presence of alcoholic KOH , alkenes are the major products.
7. Distinguish between C2H5Br and C6H5Br through chemical test .
8. What are Enantiomers and Racemic mixtures ?
9. Predict the order of reactivity of the following compounds in SN1 reaction C6H5CH2Br , C6H5CH(C6H5)Br , C6H5CH(CH3)Br , C6H5C(CH3)(C6H5)Br
10. What is chemical name of D.D.T ? How it is prepared ?