Final answer:
The bond angle in ethers is slightly less than tetrahedral due to electron pair repulsion; however, the provided reason about the bulkiness of groups is not the sole explanation. The actual bond angle is influenced by the lone pairs on oxygen and the molecular bent shape. The correct answer is option: (e) Both assertion and reason are correct statements but reason is not correct explanation of assertion.
Step-by-step explanation:
The student's question pertains to the bond angle in ethers and the reason behind its deviation from the ideal tetrahedral angle. The assertion that the bond angle in ethers is slightly less than the tetrahedral angle is correct, and this is indeed because of the repulsion between the two alkyl (-R) groups attached to the oxygen atom.
However, the reason provided as the replication between two bulky groups is not entirely accurate because ethers can have both bulky and not so bulky groups, and the deviation occurs not only because of steric hindrance but also because of the bent shape and lone pair-bond pair repulsion on the oxygen atom.
Therefore, the correct answer is choice (e): Both assertion and reason are correct statements but reason is not correct explanation of assertion. The electron-pair geometry of the oxygen atom in an ether molecule is indeed tetrahedral due to the four regions surrounding it, but the molecular structure becomes bent, leading to a bond angle slightly less than 109.5°, similar to the bond angle observed in water (104.5°).