When another atom or group of atoms is substituted for one of the hydrogen atoms in benzene, C6H6 the boiling point changes. Explain the order of the following boiling points: C₆H₆, 80 °C; C₆H₅Cl, 132 °C; C₆H₅Br, 156 °C; C₆H₅OH, 182 °C.