submerging vs immersion

submerging and immersion both are nouns.

Word	Noun	Adjective	Verb	Adverb
submerging	Yes	No	No	No
immersion	Yes	No	No	No

As nouns, submerging and immersion are synonyms defined as:

Other synonyms of submerging include submergence, submersion.

submerging (noun)	immersion (noun)
sinking until covered completely with water	a form of baptism in which part or all of a person's body is submerged
	the act of wetting something by submerging it
	complete attention; intense mental effort
	sinking until covered completely with water
	(astronomy) the disappearance of a celestial body prior to an eclipse