Electronic Effects

The most stable canonical structure of this molecule is:

In which of the following molecules / ions resonance structures are equivalent:

Among these compounds,  the correct order of C–N bond length is :

In which of the following pairs, is the first species is more stable than second?

In which of the following molecules π-electron density in ring is maximum ?

In which of the following molecules π-electron density in ring is minimum ?

Which of the following compounds has maximum electron density in ring ?

Which of the following compounds has maximum electron density in ring ?

In phenol, π - electron - density is maximum on

The order of stability of these canonical forms is:

Among these canonical structures of pyridine, the correct order of stability is

The most stable resonating structure of following compound is

$\left(\mathrm{I}\right){\mathrm{CH}}_3-\mathrm{O}-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}=\mathrm{CH}}_2$

$\left(\mathrm{II}\right){\mathrm{CH}}_3-\mathrm{O}-\stackrel{\oplus }{\mathrm{C}}\mathrm{H}-\mathrm{CH}={\mathrm{CH}-\stackrel{\ominus }{\mathrm{C}}\mathrm{H}}_2$

$\left(\mathrm{III}\right){\mathrm{CH}}_3-\stackrel{\oplus }{\mathrm{O}}=\mathrm{CH}-\mathrm{CH}={\mathrm{CH}-\stackrel{\ominus }{\mathrm{C}}\mathrm{H}}_2$

Among these three canonical structures (through more are possible) what would be their relative contribution in the hybrid?

$\begin{array}{cc}\left(\text{I}\right)& {\text{CH}}_2=\underset{\updownarrow }{\text{C}}\text{H}-\text{CH}=\text{CH}-\text{O}{\text{CH}}_3\\ \left(\text{I}\text{I}\right)& \stackrel{\ominus }{\text{C}}{\text{H}}_2-\underset{\updownarrow }{\text{C}}\text{H}=\text{CH}-\text{CH}=\stackrel{\oplus }{\text{O}}{\text{CH}}_3\\ \left(\text{III}\right)& {\text{CH}}_2=\underset{\updownarrow }{\text{C}}\text{H}-\stackrel{\ominus }{\text{C}}\text{H}-\stackrel{\oplus }{\text{C}}\text{H}-\text{O}{\text{CH}}_3\\ \left(\text{IV}\right)& {\text{CH}}_2=\text{CH}-\stackrel{\oplus }{\text{C}}\text{H}-\stackrel{\ominus }{\text{C}}\text{H}-\text{O}{\text{CH}}_3\end{array}$

Among these canonical structures which one is least stable ?

In which of the following molecules - ${\text{NO}}_2$ group is not coplanar with phenyl ring?

In which of the following molecules resonance takes place through out the entire system

Hyperconjugation involves overlap of the following orbitals

Among the following, the least stable resonance structure is

For 1–methoxy–1,3–butadiene, which of the following resonating structure is the least stable?

What is conjugation in chemistry?