Damage Types to Fire on Enemies:

in mission

Angel - Explosive
Blood - EM
Drones - EM
Gurista - Kinetic
Mercenaries - Thermal
Mordus - Thermal & Kinetic
Sansha - EM & Thermal
gellente - kinetic
EOM

http://wiki.eveonline.com/en/wiki/Damage_types

NPC Name Damage type to deal
Angel Cartel Explosive
Blood Raiders Electromagnetic/Thermal
Caldary Navy Kinetic
EoM Kinetic
Guristas Kinetic
Mercenary Thermal
Mordu's Legion Thermal/Kinetic
Sansha Electromagnetic/Thermal
Serpentis Thermal/Kinetic
The Syndicate Kinetic/Thermal
Thukker Tribe Explosive