The correct decreasing order of dipole moment in CH3Cl, CH3 Br and CH3F is

Question

The correct decreasing order of dipole moment in CH3Cl, CH3 Br and CH3F is (A) CH3F > CH3 Cl > CH3Br  (B) CH3F > CH3Br > CH3Cl  (C) CH3Cl > CH3 F > CH3Br  (D) CH3Cl > CH3 Br > CH3F

Tardigrade Admin · Accepted Answer

As we move down the group in the Periodic Table from

F

to

I

, the electronegativity of halogen decreases, therefore the polarity of the

C

?

X

bond and hence the dipole moment of the haloalkane should also decrease accordingly. But the dipole moment of

C H_{3} F

is slightly lower than that of

C H_{3} Cl

. The reason being that although the magnitude of -ve charge on the

F

atom is much higher than that on the

Cl

atom but due to small size of

F

as compared to

Cl

, the

C ? F

bond distance is so small that the product of charge and distance

(μ = q \times d)

, ie, dipole moment of

C H_{3} F

turns out to be slightly lower than that of

C H_{3} Cl

. Therefore, the order of dipole moment is

1.860 D C H_{3} Cl > 1.847 D C H_{3} F > 1.830 D C H_{3} B r

Q. The correct decreasing order of dipole moment in $C H_{3} Cl, C H_{3} B r$ and $C H_{3} F$ is

$C H_{3} F > C H_{3} Cl > C H_{3} B r$

$C H_{3} F > C H_{3} B r > C H_{3} Cl$

$C H_{3} Cl > C H_{3} F > C H_{3} B r$

$C H_{3} Cl > C H_{3} B r > C H_{3} F$

Q. The correct decreasing order of dipole moment in CH3​Cl,CH3​Br and CH3​F is

CH3​F>CH3​Cl>CH3​Br

CH3​F>CH3​Br>CH3​Cl

CH3​Cl>CH3​F>CH3​Br

CH3​Cl>CH3​Br>CH3​F

Q. The correct decreasing order of dipole moment in $C H_{3} Cl, C H_{3} B r$ and $C H_{3} F$ is

$C H_{3} F > C H_{3} Cl > C H_{3} B r$

$C H_{3} F > C H_{3} B r > C H_{3} Cl$

$C H_{3} Cl > C H_{3} F > C H_{3} B r$

$C H_{3} Cl > C H_{3} B r > C H_{3} F$