Answer:
The main difference between the Coronado and La Salle expeditions was the purpose with which each expedition began.
Thus, Coronado carried out his expedition to the southwestern United States with the objective of claiming those territories for the Spanish Empire, territories that had already been explored and in which it was expected to discover native cities full of wealth.
Instead, La Salle carried out his expedition along the Mississippi River with the goal of discovering the territories adjacent to it, and claiming them for the Kingdom of France.
Thus, while the La Salle expedition had a merely territorial and expansionist objective, the Coronado expedition had as its main objective the discovery of sumptuous wealth in the explored territories.