8. A few drops of ethanoic acid were added to solid sodium carbonate. The possible results of the
reactions are: [   ]

a) A hissing sound was evolved.                  b) Brown fumes evolved.
c) Brisk effervescence occurred.                 d) A pungent smelling gas evolved.


9. When acetic acid reacts with ethyl alcohol, we add conc.H2SO4,which acts as……….and
the process is called………………….. [  ]

a) Oxidizing agent,saponification                b) Dehydrating agent, esterification
c) Reducing agent, Esterification                d) Acid & esterification
Suggested Experiments

1. Suggest a test to find the hardness of water and explain the procedure.(AS3)

2. Suggest a chemical test to distinguish between ethanol and ethanoic acid and explain the
procedure.(AS3)

3. An organic compound ‘X’ with a molecular formula C2H6O undergoes oxidation with alkaline
KMnO4and forms the compound ‘Y’ that has molecular formula C2H4O2.(AS3)

  1. Identify ‘X’ and ‘Y’
  2. Write your observation regarding the product when the compound ‘X’ is made to
    react with compound ‘Y’ which is used as a preservative for pickles.
Suggestive Projects

1. Prepare models of methane, ethane, ethene and ethyne molecules using clay balls and match sticks. (AS4)

2. Collect information about artificial ripening of fruits by ethylene. (AS4)

3. How do you condemn the use of alcohol as a social practice. (AS7)

What is pKa?
pKa is the negative value of logarithm of dissociation constant of an acid.
pKais a measure of how much an acid dissociates in a solution.
pKa=-log10Ka
The lower the pKa value, the stronger is the acid.
pKa values are related to their dissociation in aqueous solutions. Note that pKa of 1.0M HCl is zero but pKa of CH3COOH is 4.76. pKa values are useful to tell about acid strength. Strong acids have pKa < 1, acids with pKa between 1 and 5 are moderately strong and weak acids have pKa between 5 and 15. The weakest acids have pKa > 15. Note that pKa values less than zero are not generally given as they are of no use to give in terms of pKa. They may be directly given in terms of Ka.


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