Question

Which statements are true about constitutional isomers? (a) They have the same molecular formula. (b) They have the same molecular weight. (c) They have the same order of attachment of atoms. (d) They have the same physical properties.

Short answer

Answer: Statements (a) and (b) are true about constitutional isomers. They have the same molecular formula and the same molecular weight.

Step-by-step solution

Statement a: They have the same molecular formula.

Constitutional isomers have the same molecular formula, meaning they have the same number and type of elements. This statement is true.

Statement b: They have the same molecular weight.

Since constitutional isomers have the same molecular formula, they will also have the same molecular weight due to the presence of the same number and type of elements. This statement is true.

Statement c: They have the same order of attachment of atoms.

Constitutional isomers have different connectivity of atoms, which means that the order of attachment of atoms is different among them. This statement is false.

Statement d: They have the same physical properties.

Constitutional isomers have different physical properties because their different connectivity of atoms results in different structures and, consequently, their properties vary. This statement is false. In conclusion, statements (a) and (b) are true about constitutional isomers, while statements (c) and (d) are false.