Why did Moshe use the title "Elokei ha'Ruchos"?
Rashi: Assuming (mistakenly) that Hashem was about to destroy all of Yisrael, Moshe pointed out that following a rebellion, human kings, cannot distinguish between those who sinned and those who didn't, and punish them all, but Hashem is able to distinguish between tose who sinned and those who didn't. 1
Rashbam: He meant that Hashem knows the hearts and the minds of tho rest of the people who did not sin.
What did Moshe set out to achieve with his Tefilah?
Rashi and Ramban #1 (citing R. Chananel): He Davened that Hashem should change His mind and punish only Korach (and his congregation ? Ramban, ibid.) 1
Ramban #2 and Targum Yonasan: He set out to remove the punishment from the people 2 and to place it fairly and squarely on the shoulders of Korach and his henchmen, who were directly responsible for the rebellion, as is the way of those who plead for mercy on behalf of the masses. 3
Seforno: He set out to remove the punishment from the people and to place it fairly and squarely on the shoulders of Korach, who incited the congregtion to rise up against him and Aharon. 4
Seeing as the entire congregation had assembled against Moshe, why did Moshe say ?ha?Ish Echad Yecheta??
Refer to 16:22:2:3.