Vapour phase nitration of propane yields

1-nitropropane + 2-nitropropane + nitroethane + nitromethane

The correct answer is option 3. 1-nitropropane + 2-nitropropane + nitroethane + nitromethane.

Vapour phase nitration of propane is a reaction that involves the introduction of a nitro group (-NO2) to the propane molecule in the gas phase, typically using nitric acid or nitrogen dioxide at high temperatures. This reaction can yield a mixture of products because different carbon atoms in propane can be nitrated.

Propane (\(C_3H_8\)) has the following structure: \(H_3C-CH_2-CH_3 \)

When propane undergoes nitration in the vapor phase, it primarily yields 1-nitropropane and 2-nitropropane as the main products. Additionally, at high temperatures, the reaction can also lead to further fragmentation and formation of smaller nitro compounds such as nitroethane and nitromethane.

Possible Products:

1-nitropropane (\(CH_3CH_2CH_2NO_2\)): Nitration occurs at the primary carbon (first carbon).

2-nitropropane (\(CH_3CH(NO_2)CH_3\)): Nitration occurs at the secondary carbon (second carbon).

Nitroethane (\(CH_3CH_2NO_2\)): Formed by fragmentation of the propane chain.

Nitromethane (\(CH_3NO_2\)): Formed by further fragmentation.

During the vapor phase nitration of propane, the reaction does not just stop at forming 1-nitropropane and 2-nitropropane but can also produce smaller nitro compounds like nitroethane and nitromethane due to the high energy conditions leading to fragmentation of the propane molecule. Therefore, the correct answer is: (3) 1-nitropropane + 2-nitropropane + nitroethane + nitromethane This option correctly represents the mixture of products formed during the vapor phase nitration of propane.