Assertion: Chemical formula of n-propane and isopropane is the same.Reason: n-propane does not exhibit chain isomerism.A.Both assertion and reason are correct and reason is the correct explanation of assertion.B.Both assertion and reason are correct but reason is not the correct explanation for assertion.C.Assertion is incorrect but reason is correct.D.Both assertion and reason are incorrect.

The assertion and reason provided are both incorrect.

The chemical formula of n-propane (normal propane) and isopropane (also known as 2-propane) is not the same.
The chemical formula for n-propane is C3H8.
The chemical formula for isopropane is also C3H8, but their structural arrangements are different.
N-propane does exhibit chain isomerism. Chain isomerism occurs when different structural isomers have the same molecular formula but different arrangements of atoms in the carbon skeleton. In the case of n-propane and isopropane, they are structural isomers, which means they have the same molecular formula but different arrangements of atoms.
So, the correct answer is option D: Both assertion and reason are incorrect.