There were several kinds of explosive ordnance used at Pearl Harbor by the Japanese. The variety was designed to destroy several different targets that the Japanese aviators expected to encounter during their attack.

The Japanese bombers were equipped to target the American fleet that was moored at the naval base there, as well as a variety of land targets, such as grounded aircraft and military installations.

The Type 99 #80 mark 5 800kg bomb and the Type 99 #25 Model 1 Ordinary Bomb 250kg were designed to puncture the decks of the American ships and detonate inside the hulls.

Many of the Japanese bombers were also equipped with the Type 91 Modification 2 800kg torpedo, which could be released into the water to propel itself into the hull of its intended target. 

The Type 98 #25 250kg Land Bomb and the Type 97 #6 60kg Land Bomb were designed to detonate on impact and were used to disable planes and ground installations on land around the harbor.

The Japanese were well armed to destroy the American military resources at Pearl Harbor. The fact that the American aircraft carrier fleet was away at sea trials mitigated what was otherwise a devastating blow.