Overlaps Taking All Together

Q. Postulates of vbt &vsepr

Q.

What are the major drawbacks of the Valence bond theory?

Q. $d\pi -p\pi$ bond present in:

1. $C{O}_3^{2-}$
2. $P{O}_4^{3-}$
3. $N{O}_3^{-}$
4. $N{O}_2^{-}$

Q.

Considering x-axis as the internuclear axis which out of the following will not form a sigma bond and why? (a) 1s and 1s (b) 1s and 2p_x (c) 2p_y and 2p_y (d) 1s and 2s.

Q.

What are the Applications of Valence Bond Theory?

Q. $p\pi -d\pi$ back bonding cannot occur in:

1. $P{F}_3$
2. $As{F}_3$
3. $O(Si{H}_3{)}_2$
4. $B{F}_3$

Q. In molecular orbital theory the energy level change when we move from N2 to o2. Why?

Q.

Most efficient overlapping is

(a)$s{p}^2$−$s{p}^2$

(b)$s{p}^3$−$s{p}^3$

(c)s−s

(d)sp−sp

Explain

Q.

What is VSEPR THEORY used for??

Q. According to VBT, the direction of a bond which is formed due to overlapping will be_________

1. In the same direction in which orbitals are concentrated
2. In the opposite direction in which orbitals are concentrated
3. Perpendicular to the direction in which orbitals are concentrated
4. None of the mentioned

Q.

Assuming the bond direction to be Z-axis, which of the overlapping of atomic orbitals of two atoms A and B will be result in bonding; (I) s orbital of A and $p_x$ orbital of B, (II) s orbital of A and $p_z$ orbital of B (III) $p_y$ orbital of A and $p_z$ orbital of B, (IV) s- orbitals of A and B

1. II
2. III
3. I
4. II & IV

Q. Which of the following overlapping will result in the formation of strongest bond?

1. 

2. 

3. 

4. 

Q.

What is molecular orbital?

Q. The donation of lone pair of electrons of $CO$ carbon into the vacant orbital of metal atom results in _______.

1. $\sigma$- bond
2. synergic bond
3. back bond
4. $\pi$-bond

Q. Which of the following leads to bonding?

1. 
2. 
3. 
4. 

Q.

Which of the following depicts '-ve' overlapping?

1. 

2. 

3. 

4. None of these

Q. Explain the following:


A) $C{O}_2$ is a gas whereas $Si{O}_2$ is a solid.

B)Silicon forms $[Si{F}_6{]}^{2-}$ ion whereas the corresponding fluoro compound of carbon is not known.

Q. Boron fluoride exists as $B{F}_3$ but boron hydride doesn’t exist as $B{H}_3$. Give a reason. In which form does it exist? Explain its structure.

Q.

Predict the shapes of the following molecules on the basis of hybridisation.

$BC{l}_3,C{H}_4,C{O}_2,N{H}_3$.

Q. Which of the following molecule have only one $p\pi -d\pi$ bond and zero $p\pi -p\pi$ bonds?

1. $Cl{O}_3^{-}$
2. $S{O}_2$
3. $Cl{F}_3$
4. $S{O}_3^{2-}$

Q.

Explain the bond formation between, ${\mathrm{NH}}_3$ and ${\mathrm{CH}}_4$ (VBT)?

Q. Which of the following has the least Lewis acidic character?

1. $B{F}_3$
2. $BC{l}_3$
3. $BB{r}_3$
4. All have the same acidic character

Q. Statement 1: $N{Me}_3$ and $N{\left(Si{Me}_3\right)}_3$ are not isostructural.
Statement 2: $N{Me}_3$ and $N{\left(Si{Me}_3\right)}_3$ have the same steric number.

Regarding the above statements which of the following is/are correct?

1. Both the statements are true
2. Both the statements are false
3. Only statement 1 is true
4. Only statement 2 is true

Q.

The bond, in compound formed from combination of 14 group and 17 group elements of Periodic table will be

1. Electrovalent bond

2. Co-ordinate bond

3. Vander Waals bond

4. Covalent bond

Q. The orbitals that can form $\delta$ bond among the following is:

1. s
2. p
3. d
4. None of the above

Q. What is the importance of valence bond theory?

Q.

Which one of the compounds is not known?

1. ${\mathrm{NCl}}_5$

2. ${\mathrm{PCl}}_5$

3. ${\mathrm{AsCl}}_5$

4. ${\mathrm{NCl}}_3$

Q. Which of the following statements is correct regarding the complex, $\left[Cr\right(N{H}_3{)}_6{]}^{3+}$?

1. Both B and C
2. Involves $d^{2}s{p}^3$ hybridisation
3. It is an outer orbital complex
4. It is an inner orbital complex

Q. Which of the following is not true for $N(Si{Me}_3{)}_3$?

1. The lone pair of electrons occupy a $p$-orbital at right angles to the plane triangle and this overlaps with the empty $p$-orbitals on each of the three $Si$ atoms resulting in $\pi$ bonding
2. Three $s{p}^2$ orbitals are used for sigma bonding, giving a plane triangular structure
3. The $N-Si$ bond length is shorter than expected $N-Si$ bond length.
4. It is a weaker Lewis base than tri methyl amine

Q.

What is the name of the bond formed when a metal atom combines with the atom of a non-metal?