The most stable conformation of the following compound is

Which one of the following is most reactive towards electrophilic reagent?

In the projection formula $[A]$,two groups ($Br$ and $CH_3$) at the chiral center are interchanged to obtain formula $[B]$. When two groups ($C_2H_5$ and $Cl$) of $[A]$ are interchanged,the projection formula $[C]$ is obtained. Which of the following statements is $NOT$ correct for $[A]$,$[B]$,and $[C]$?

Which of the following compounds is chiral but does not contain a chiral carbon?

Which of the following shows keto-enol isomerism?

Find out the statements which are not true.
$A$. Resonating structure with more number of covalent bonds and lesser charge separation are more stable.
$B$. In electromeric effect, an unsaturated system shows $+E$ effect with nucleophile and $-E$ effect with electrophile.
$C$. Inductive effect is responsible for high melting point, boiling point and dipole moment of polar compounds.
$D$. The greater the number of alkyl groups attached to the doubly bonded carbon atoms, higher is the heat of hydrogenation.
$E$. Stability of carbanion increases with the increase in $s$-character of the carbon carrying the negative charge.
Choose the correct answer from the options given below.