Final answer:
None of the options A) CH₃CH₂OCH₂CH₃, B) CH₃OCH₂CH₃, C) CH₃CH₃, or D) CH₃OCH₃ provided are correct isomers for the given compounds as they do not have identical molecular formulas with different arrangements.
Step-by-step explanation:
The student's question pertains to the identification of isomers for certain molecular formulas. Isomers are compounds with the same molecular formula but different arrangements of atoms. The molecular formula given by the student for part (a) is CH₃CH3, which is ethane, and part (b) is CH₃OCH₃, which is dimethyl ether. The correct isomer for ethane (CH₃CH3) would be another compound with two carbons and six hydrogens, however, none of the options provided are isomers of ethane. All the options contain different elements or are functional group isomers, not chain isomers.
In the case of dimethyl ether (CH₃OCH₃), the compounds that could potentially be isomers are ones with the same molecular formula but different structures, like ethanol (CH₃CH₂OH). Again, the options provided do not include ethanol or any other molecule with the same molecular formula arranged differently. Therefore, none of the options A) CH₃CH₂OCH₂CH₃, B) CH₃OCH₂CH₃, C) CH₃CH₃, or D) CH₃OCH₃ are correct isomers for the given compounds, as they do not have identical formulas. The presence of tetrahedral carbon or trigonal planar central carbon structures, as mentioned in the provided information, are important in understanding the geometry of molecules but are not directly relevant to the identification of isomers for the given question.