Oxidation of ketones involves carbon-carbon bond cleavage. Name the products formed on oxidation of 2, 5-dimethylhexan-3-one.
According to Popoff's rule, the unsymmetrical ketone on oxidation, $\mathrm{C}-\mathrm{C}$ bond cleavage and keto group goes with 
Arrange the following in decreasing order of their acidic strength and give reason for your answer.
$$\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH}, \mathrm{CH}_3 \mathrm{COOH}, \mathrm{ClCH}_2 \mathrm{COOH}, \mathrm{FCH}_2 \mathrm{COOH}, \mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{COOH}$$
$$\mathrm{FCH}_2 \mathrm{COOH}>\mathrm{ClCH}_2 \mathrm{COOH}>\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{COOH}>\mathrm{CH}_3 \mathrm{COOH}>\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{OH}$$
Reasons
(i) More the electron withdrawing nature of substituent, more is the acidic strength.
(ii) Direct attachment of $\mathrm{C}_6 \mathrm{H}_5$ group increases acidity due to resonance and $s p^2$ hybridisation.
(iii) Alcohols are weakly acidic than carboxylic acids.
What product will be formed on reaction of propanal with 2-methylpropanal in the presence of NaOH ? What products will be formed? Write the name of the reaction also.
It is an example of cross aldol condensation.
Compound ' $A$ ' was prepared by oxidation of compound ' $B$ ' with alkaline $\mathrm{KMnO}_4$. Compound ' $A$ ' on reduction with lithium aluminium hydride gets converted back to compound ' B '. When compound ' A ' is heated with compound $B$ in the presence of $\mathrm{H}_2 \mathrm{SO}_4$ it produces fruity smell of compound C to which family the compounds ' A ', ' B ' and ' C ' belong to?
Since, B and A on heating together in the presence of acid produces ester (a fruity smell).
Arrange the following in decreasing order of their acidic strength. Give explanation for the arrangement.
$$\mathrm{C}_6 \mathrm{H}_5 \mathrm{COOH}, \mathrm{FCH}_2 \mathrm{COOH}, \mathrm{NO}_2 \mathrm{CH}_2 \mathrm{COOH}$$
The decreasing order of their acidic strength
$$\mathrm{NO}_2 \mathrm{CH}_2 \mathrm{COOH}>\mathrm{FCH}_2 \mathrm{COOH}>\mathrm{C}_6 \mathrm{H}_5 \mathrm{COOH}$$
Acidic strength decreases as the number of electron withdrawing substituent(s) linked to $\alpha$-carbon atom or carboxylic group of carboxylic acid decreases. Electron withdrawing ability of $\mathrm{NO}_2, \mathrm{~F}$ and $\mathrm{C}_6 \mathrm{H}_5$ are as follows
$$-\mathrm{NO}_2>-\mathrm{F}>\mathrm{C}_6 \mathrm{H}_5-$$