$H_{2}O$ has a net dipole moment while Be$F_2$ has zero dipole moment because :

(1) F is more electronegativity than oxygen 

(2) Be is more electronegativity than oxygen 

(3) $H_{2}O<mspace\; width="1em"></mspace>$ molecule is linear and Be$F_2$ is bent 

(4) $Be{F}_2$ molecule is linear and $H_{2}O$ is bent

How many sigma bonds are in a molecule of diethyl ether, $C_2{H}_{5}O{C}_2{H}_5$

1. 14         

2. 12         

3. 8         

4. 16

In which molecule does the chlorine atom has positive partial charge? 

(1) HCl

(2) BrCl 

(3) $OC{l}_2$

(4) $SC{l}_2$

Which of the following is a pair of polar molecules?

1. ${\mathrm{CO}}_2$ $\mathrm{and}$ ${\mathrm{H}}_2\mathrm{O}$

2. ${\mathrm{BF}}_3$ $\mathrm{and}$ ${\mathrm{PCl}}_3$

3. ${\mathrm{SO}}_2$ $\mathrm{and}$ ${\mathrm{SCl}}_2$

4. ${\mathrm{CS}}_2$ $\mathrm{and}$ ${\mathrm{SO}}_3$

Which of the following species has a zero dipole moment?

$\left(\mathrm{i}\right)$ ${\mathrm{CO}}_2$ (ii) ${\mathrm{COCl}}_2$ (iii) ${\mathrm{CH}}_2$ ${\mathrm{Cl}}_2$ (iv) ${\mathrm{BCl}}_3$

The incorrect order of lattice energy among the following set is:

1. ${\mathrm{AlF}}_3>{\mathrm{MgF}}_2$         

2. ${\mathrm{Li}}_3\mathrm{N}>{\mathrm{Li}}_2\mathrm{O}$

3. $\mathrm{NaCl}>\mathrm{LiF}$           

4. $\mathrm{TiC}>\mathrm{ScN}$

Which of the following overlops is incorrect (assuming Z axis internuclear axis)?

(A) $2p_{y<mspace\; width="1em"></mspace>}+2p_y\to \pi ‐Bond<mspace\; width="1em"></mspace>formation$        (B) $2p_x+2p_x\to \sigma ‐Bond<mspace\; width="1em"></mspace>formation$

(C) $3d_{xy}+3d_{xy}\to \pi ‐<mspace\; width="1em"></mspace>Bond<mspace\; width="1em"></mspace>formation$        (D) $2s+2p_y\to \pi ‐Bond<mspace\; width="1em"></mspace>formation$

(E)$3d_{xy}+3d_{xy}\to \delta Bond<mspace\; width="1em"></mspace>formation$             (F)$2p_z+2p_z\to \sigma <mspace\; width="1em"></mspace>Bond<mspace\; width="1em"></mspace>formation$

(a) A,B,C                      (b) C,F

(c) B,E                         (D) B,C,D

The correct statement about carbene $\left(C{H}_2\right)$ is:

(1) In singlet carbene, carbon is $s{p}_2$-hybridized whereas in triplet carbene, carbon is sp-hybridized

(2) Triplet carbene is less stable than singlet carbene

(3) Stability of halocarbenes is: CHF>CHCL>CHBr

(4) None of the above

The incorrect statement(s) regarding ${\mathrm{CX}}_3$ species is:

(1) If electronegativity of surrounding element 'X' is less than 2.5, then central carbon atom used almost 33% s-character in their hybrid bonding orbitals

(2) If electronegativity of surrounding element 'X' is more than 2.5, then central carbon atom used almost 25% s-character in their hybrid bonding orbitals

(3) If 'X' is 'F', then species should be polar and pyramidal

(4) If 'X' is H, then species should be polar and planar