17.2 The elemental substances 1.Physical properties of the elemental substances: F2 C12 Br2 12 State of aggregation g g Intermolecular force small large b.p./℃ -188 -34 59 185 m.p./℃ -220 -102 -7 114 Color pale yellow red-brown yellow-green dark red 1.Physical properties of the elemental substances： State of aggregation g g l s b.p./℃ -188 -34 59 185 m.p. /℃ -220 -102 -7 114 Color pale yellow red-brown yellow-green dark red Intermolecular force small large F2 Cl2 Br2 I2 17.2 The elemental substances