Draw structural formulas for (a) phenol (b) o-bromochlorobenzene (c) 1,3-dichloro-5-nitrobenzene (d) \(m\)-dinitrobenzene

Understanding the structural formula of phenol is fundamental in organic chemistry. Phenol, often recognized by its IUPAC name as 'hydroxybenzene,' comprises a benzene ring which is a stable structure with alternating double and single bonds.

In phenol, one hydrogen atom of the benzene ring is replaced by a hydroxyl group (-OH), which is responsible for its unique properties. The hydroxyl group, being polar, can form hydrogen bonds, which significantly contribute to the relatively higher boiling point of phenol compared to other hydrocarbons of similar molecular weight.

Phenols are precursors to many industrial compounds and are particularly important in the manufacture of plastics and pharmaceuticals. When studying its structure, it’s important to place the hydroxyl group directly attached to the benzene ring and not on a separate carbon chain.

Ortho-bromochlorobenzene represents an interesting example of disubstituted benzene derivatives. In this compound, you have both bromine (Br) and chlorine (Cl) attached to the benzene ring. The 'ortho-' designation tells us that these two substituent atoms are neighbors, meaning they are bonded to adjacent carbon atoms in the six-membered ring.

In drawing ortho-bromochlorobenzene, it's important to start with the benzene ring, then correctly position the bromine and chlorine at the 1 and 2 positions, or equivalently, the 2 and 1 positions due to symmetry. This compound is used in organic synthesis and is also a key substance in understanding the effects of substituents on the reactivity and properties of benzene derivatives.

The structure of 1,3-dichloro-5-nitrobenzene is characterized by specific functional groups attached to a benzene ring at designated locations. This compound features two chlorine (Cl) atoms and one nitro group (-NO2), with the numbers in the name indicating their positions on the ring.

It's crucial to identify the correct carbon atoms for attachment of the substituents to comprehend the structure accurately. The two chlorines are at the 1 and 3 positions, and the nitro group is at the 5 position. Remembering the order might seem complex, but visualizing the benzene ring and numbering the positions starting from one substituent until you've placed all groups can simplify the task. 1,3-Dichloro-5-nitrobenzene is a useful compound in the field of dyes and pigments, and its structure is a prime example of how substituents can influence the properties of molecules in organic chemistry.

Meta-dinitrobenzene is an aromatic compound with two nitro groups (-NO2) attached to a benzene ring. The 'meta-' terminology refers to the positioning of the substituents, which are separated by a single carbon atom; they’re not adjacent nor opposite each other on the benzene ring.

When drawing meta-dinitrobenzene, the two nitro groups should be placed at the 1 and 3 positions, or any equivalent ring positions that maintain the one-carbon separation. This structure is significant in demonstrating how substituent positioning influences a compound's chemical reactivity and its physical properties, such as melting point and solubility. Meta-dinitrobenzene is also present in various chemical manufacturing processes and serves as a stepping stone to more complex chemical syntheses.