-NO2 > -CN > -COOH > -COOR

-CN > -NO2 > -COOH > -COOR

-COOH > -COOR > -NO2 > -CN

-COOR > -COOH > -CN > -NO2

$- {\rm{COOH}}$

$- {\rm{C}}{{\rm{H}}_3}$

$- {\rm{C}}{{\rm{H}}_3}{\rm{C}}{{\rm{H}}_2}$

$- {\rm{CH}}{R_2}$

$- {\rm{N}}{{\rm{O}}_2}$

$- {\rm{CN}}$

$- {\rm{COOH}}$

$- {\rm{F}}$

${\rm{C}} - {\rm{O}}$

${\rm{C}} - {\rm{C}}$

${\rm{C}} - {\rm{H}}$

${\rm{O}} - {\rm{H}}$

I > II > III > IV

II > I > IV > III

III > IV > I > II

IV > III > II > I

$\overline C {H_2} - C{H_2} - N{O_2}$

$\overline C {H_2} - C{H_2} - CN$

$\overline C {H_2} - C{H_2} - COOH$

$\overline C {H_2} - C{H_2} - C{H_2} - C{H_2} - F$

The chlorine atom with the positive charge (Cl⁺)

The neutral chlorine atom (Cl)

They have the same electronegativity

Chlorine atoms cannot have a positive charge

${{\rm{C}}_2}{\rm{H}}_5^ -$

${{\rm{C}}_2}{{\rm{H}}_5}{\rm{CO}}{{\rm{O}}^ - }$

${{\rm{C}}_2}{{\rm{H}}_5}{{\rm{O}}^ - }$

${{\rm{H}}_2}{\rm{P}}{{\rm{O}}_4}$

Electron-withdrawing groups like halogens exhibit a $-I$ effect.

Alkyl groups ($-R$) exhibit a $-I$ effect.

The $+I$ effect increases with increasing electronegativity of the substituent.

The $-I$ effect is transmitted through pi bonds.

$-CH_3$

$-NH_2$

$-OH$

$-NF_3^+$

II > I > IV > III

III > IV > I > II

IV > III > II > I

I > II > III > IV