Resonance

Q. Which of the following bonds/forces is the weakest?

1. Covalent bond
2. Ionic bond
3. Hydrogen bond
4. London force

Q. All $C-C$ bonds in benzene are equal due to

1. Tautomerism
2. Inductive effect
3. Resonance
4. Isomerism

Q. Resonance is not shown by:

1. $Cl{O}_4^{-}$
2. $S{O}_3$
3. $CC{l}_4$
4. Both B and C

Q. In the following molecule, the $C_2-C_3$ bond length is shorter than the usual $C-C$ bond length. The reason for this observation is ______
$C=\underset{\left(2\right)}{C}-\underset{\left(3\right)}{C}=C$

1. Odd electrons
2. Incomplete octet
3. Resonance
4. Extented Octet

Q. How many resonance structures does $C{O}_2$ have?

1. 2
2. 3
3. 4
4. 5

Q. Resonance involves
(a) migration of an H atom
(b) delocalisation of $\sigma$ electrons
(c) delocalisation of $\pi$ - electrons
(d) migration of alkyl group
The correct answer is

1. A, B
2. C, D
3. C only
4. D only

Q. How many resonance forms can be written for the nitrate ion $\left(N{O}_3^{-}\right)$?

1. 1
2. 2
3. 3
4. 4

Q. Which of the following is correct regarding the bond order in $S{O}_4^{2-}$ ion?

1. 3/2
2. 5/4
3. 4/3
4. 2

Q.

The correct increasing order of acidity is:

1. $H_{2}O,C_2{H}_2,H_{2}C{O}_3,phenol$

2. $C_2{H}_2,H_{2}O,H_{2}C{O}_3,phenol$

3. $Phenol,C_2{H}_2,H_{2}C{O}_3,H_{2}O$

4. $C_2{H}_2,H_{2}O,phenol,H_{2}C{O}_3$

Q. How many resonance structures does $C{O}_2$ have?

1. 2
2. 3
3. 4
4. 5

Q.

Predict the relative bond lengths a and b, in napthalene

1. a > b

2. a < b
   

3. a = b

4. none of these

Q. The number of resonance structures possible in ozone (O3) is .

1. 3
2. 1
3. 2

Q. The most acidic among the following is:

1. $N{H}_3$
2. $C{H}_{3}CON{H}_2$
3. $C_6{H}_{5}CON{H}_2$
4. $Ph-\stackrel{O}{\stackrel{||}{C}}-NH-\stackrel{O}{\stackrel{||}{C}}-Ph$

Q. Azide ion $\left[N_3^{-}\right]$ exhibits an $(N-N)$ bond order of $2$ and may be represented by the resonance structures $I,II$ and $III$ given below:

The most stable resonance structure is

1. I
2. II
3. III
4. All of them have equal stability

Q.

Explain the following:

Q. Strength of acidic nature is in order.

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

Q. How many resonance structures are possible in $O_3$?

1. 2

2. 3

3. 1

4. 4

Q. Resonance involves
(a) migration of an H atom
(b) delocalisation of $\sigma$ electrons
(c) delocalisation of $\pi$ - electrons
(d) migration of alkyl group
The correct answer is

1. A, B
2. C, D
3. C only
4. D only

Q. Assertion: $C{O}_2$ is a resonance stabilized molecule.
Reason: The bond length of $C-O$ in $C{O}_2$ is in between the lengths of a single and a double bond.

1. Both the assertion and the reason are true and the reason is the correct explanation of the assertion.
2. Both the assertion and the reason are true but the reason is not the correct explanation of the assertion.
3. The assertion is true but the reason is false.
4. Both the assertion and the reason are false.

Q.
The correct relation between the bond lengths of (a) and (b) is:

1. a = b
2. b > a
3. b< a
4. Impossible to predict