Final answer:
p-Tolualdehyde is more reactive towards nucleophilic addition reactions compared to p-nitrobenzaldehyde because it has an electron-donating methyl group that increases the electron density on the carbonyl carbon, facilitating nucleophilic attack.
Step-by-step explanation:
Out of p-tolualdehyde and p-nitrobenzaldehyde, p-tolualdehyde is more reactive towards nucleophilic addition reactions. The reason behind this is the electron-donating methyl group attached to the benzene ring in p-tolualdehyde. This methyl group donates electrons through resonance and inductive effects, increasing the electron density on the carbonyl carbon, thereby making it more susceptible to nucleophilic attack.
On the other hand, p-nitrobenzaldehyde has an electron-withdrawing nitro group. This nitro group draws electrons away from the carbonyl carbon, making it less reactive to nucleophile addition as the carbonyl carbon becomes more deficient in electrons.
Thus, the correct answer to the question would be:
- p-Tolualdehyde, due to the electron-donating methyl group.