Explain how does the –OH group attached to a carbon of benzene ring activate it towards electrophilic substitution?
The -OH group is an electron-donating group. Thus, it increases the electron density in the benzene ring as shown in the given resonance structure of phenol. As a result, the benzene ring is activated towards electrophilic substitution.

Arrange the following compounds in increasing order of their boiling points:

The reaction 
suggests that phenol is :
In the reaction R–OH + HCl $\xrightarrow{\text{ZnCl}_2}$ RCl + H$_2$O, what is the correct order of reactivity of alcohols?

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?
Alcohols, phenols, and ethers are organic compounds that can be classified based on their molecular structure and functional groups.
Classification of Alcohols:
Classification of Phenols:
Classification of Ethers:
In summary, alcohols, phenols, and ethers can be classified based on their molecular structure and functional groups. Understanding the classification of these compounds is important for predicting their reactivity and understanding their potential applications in various fields, including chemistry, biology, and industry.