Question

Given below are two statements: Statement (I):

are isomeric compounds.
Statement (II):

are functional group isomers.
In the light of the above statements, choose the correct answer from the options given below:

• A. Both Statement I and Statement II are true
• B. Statement I is false but Statement II is true
• C. Statement I is true but Statement II is false
• D. Both Statement I and Statement II are false

Hint:

Always carefully analyze the functional groups in a compound and check for structural differences when dealing with isomers or functional group isomers.

Answer 1

The Correct Option is D

To determine the validity of both statements regarding isomeric compounds, let's examine them carefully:

Statement (I): The given compounds are claimed to be isomers. For compounds to be isomers, they must have the same molecular formula but differ in structure or configuration. By inspecting the molecular structures of the compounds in Statement (I), observe their molecular formulas to confirm if they match. If their formulas are different or their structural similarity does not align with the definition of isomerism, the statement is false.

Statement (II): The given compounds are claimed to be functional group isomers. Functional group isomers are a type of isomer where compounds with the same molecular formula contain different functional groups. Again, inspect the structures provided; compare their functional groups and molecular formulas. If the functional groups differ while maintaining identical molecular formulas, they are functional group isomers. However, if this is not the case, then the statement is false.

Upon analysis:

Comparison Criteria	Statement I	Statement II
Molecular Formula	Different	Same, but functional group not varied properly
Structure/Functional Group	Inconsistent with criteria for isomerism	Incorrect as proposed functional shift is not observed

Conclusion: Through the assessment of both molecular formulas and structural comparison, neither statement meets the isomer criteria. Therefore, both Statement I and Statement II are false.

Answer 2

Step 1: Analyze Statement (I).
Statement (I) shows two compounds: one is methylcyclobutane and the other is pentane.
Let’s compare their molecular formulas:
- Methylcyclobutane → \( C_5H_{10} \)
- Pentane → \( C_5H_{12} \)
Since their molecular formulas are different, they cannot be isomers of each other.
Hence, Statement (I) is false.

Step 2: Analyze Statement (II).
Statement (II) shows two compounds — one with an amine group (–NH₂) and the other with an amide group (–CONH–).
Functional group isomerism exists only when compounds have the same molecular formula but different functional groups.
Here, the number of atoms in the two compounds is not the same, so they are not functional group isomers.
Hence, Statement (II) is also false.

Step 3: Final Answer.
Since both statements are incorrect:
\[ \boxed{\text{Both Statement I and Statement II are false.}} \]