Question

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Cis form of alkene is found to be more polar than the trans form
Reason (R): Dipole moment of trans isomer of 2-butene is zero. In the light of the above statements.
Choose the correct answer from the options given below :

• A. Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
• B. (A) is true but (R) is false
• C. Both (A) and (R) are true and (R) is the correct explanation of (A)
• D. (A) is false but (R) is true

Answer 1

The Correct Option is C

The dipole moment is a vector. For trans-2-butene, the substituent dipoles cancel due to equal magnitude and opposite direction, yielding a net dipole moment of zero (\(\mu = 0\)). Conversely, in the cis isomer, these dipoles do not cancel, rendering the molecule polar with \(\mu > 0\). Consequently, the cis isomer possesses a larger dipole moment than the trans isomer.

Cis isomer: \(\mu > 0\),   Trans isomer: \(\mu = 0\).

Both the assertion and the reason are accurate, with the reason providing a correct explanation for the assertion.