JEE Advanced (True/False): Chemical Bonding & Molecular Structure | Chapter-wise Tests for JEE Main & Advanced PDF Download

Q.1. Linear overlap of two atomic p-orbitals leads to a sigma bon d. (1983 - 1 Mark) 

Ans. Sol. True : Sigma bond is formed by the overlapping of two s-orbitals or one s and one p or the two p orbitals of the two different atoms. Thus linear overlap of two p-orbitals results in formation of a σ– bond.

Q.2. All molecules with polar bonds have dipole moment. (1985 - ½ Mark) 

Ans. Sol. False : Symmetrical molecules with polar bonds have zero dipole moment.

Q.3. SnCl₂ is a non-linear molecule. (1985 - ½ Mark)

Ans. Sol. True : SnCl₂ has 2 bond pairs and one lone pair of electrons.
It is sp² hybridised and is trigonal planar in shape.

Q. 4. In benzene, carbon uses all the three p -orbitals for hybridisation. (1987 - 1 Mark) 

Ans. Sol. False : Only two orbitals are used since C in benzene is in sp² hybridised state.

Q.5. sp² hybrid orbitals have equal s and p character. (1987 - 1 Mark) 

Ans. Sol. False : sp² hybrid orbitals do not have equal s and p character.
They have 33.3% s-character and 66.7% p-character

Q.6. The presence of polar bonds in a poly-atomic molecule suggests that the molecule has non-zero dipole moment. (1990 - 1 Mark) 

Ans. Sol. False : The presence of polar bonds in a polyatomic molecule does not always lead to a definite dipole moment. This is because the dipole moment is a vector quantity and when the bond moment of one bond is cancelled by the equal but opposite bond moment due to other bond(s), the molecule has zero dipole moment, e.g. CO₂, CH₄, CCl₄ etc.

Q.7. The dipole moment of CH₃F is greater than that of CH ₃Cl. (1993 - 1  Mark)

Ans. Sol. False : The C – F distance is less than the C – Cl, although the former involves more charge separation. However, here bond distance has more dominating effect causing dipole moment of CH₃Cl to be more than that of CH₃F.