VARDAAN LEARNING INSTITUTE

1. Distinguishing Test: Give a chemical test to distinguish between:
   (a) Ethane and Ethene (Saturated vs Unsaturated)
   (b) Ethanol and Ethanoic Acid
   (c) Soap and Detergent
2. Ester Hydrolysis: An ester has the molecular formula $C_4H_8O_2$. On heating with sodium hydroxide solution, it gives sodium ethanoate and a compound 'A'.
   (a) Identify the ester and 'A'.
   (b) Write the chemical equation.
3. Hard Water Action: Explain the formation of scum when hard water is treated with soap. Write the chemical equation assuming hard water contains Calcium Chloride ($CaCl_2$) and soap is Sodium Stearate ($C_{17}H_{35}COONa$).
4. Write the electron dot structure of Cyclopentane ($C_5H_{10}$). How is it different from Pentane and Pentene?
5. Identify the compounds A to E in the following reaction sequence:
   $CH_3CH_2OH \xrightarrow{KMnO_4} A$
   $CH_3CH_2OH + A \xrightarrow{Conc.H_2SO_4} B$
   $B + NaOH \rightarrow C + CH_3CH_2OH$

Case I: Cleansing Action. Soaps are sodium or potassium salts of long chain carboxylic acids. The long hydrocarbon chain is hydrophobic while the ionic end is hydrophilic. This orientation helps in forming clusters called micelles.

6. What prevents the micelles from coming together and precipitating? (Ion-ion repulsion).
7. Why does soap solution appear cloudy? (Light scattering by colloidal micelles).
8. Can we use soap to wash clothes in acidic water? Why or why not?
9. Draw a labeled diagram of a micelle entrapping an oil droplet.

Case II: Carbon Allotropes. Carbon shows allotropy. The three allotropes are Diamond, Graphite and Fullerene. They have different physical properties but same chemical properties.

10. Why does Graphite conduct electricity but Diamond does not? Explain on basis of structure.
11. What happens when Diamond is strongly heated in air? Write the equation.
12. Why is Diamond used for cutting glass?
13. How many hexagonal and pentagonal rings are present in C-60 fullerene? (Advanced Knowledge: 20 Hexagons, 12 Pentagons).

14. Conversion: How will you bring about the following conversions?
    (a) Ethanol to Ethene
    (b) Ethanol to Ethanoic Acid
    (c) Ethene to Ethane
15. Biodegradability: Detergents with long branched hydrocarbon chains are non-biodegradable and cause water pollution. Why do bacteria find it difficult to degrade branched chains?
16. Benzene Structure: Benzene ($C_6H_6$) has alternate double bonds. Draw its structure. How many $\sigma$ (sigma) and $\pi$ (pi) bonds are present? (Recall: Single bond = 1 $\sigma$, Double bond = 1 $\sigma$ + 1 $\pi$).
17. Why is Ethanoic Acid called Glacial Acetic Acid?
18. Explain why Carbon forms strong bonds with most other elements. (Small size of atom).