open vs spread out

open is a noun but spread out is not a noun.

Word	Noun	Adjective	Verb	Adverb
open	Yes	Yes	Yes	No
spread out	No	No	Yes	No

As verbs, open and spread out are synonyms defined as:

Other synonyms of open include spread, unfold.

open (noun)	spread out (noun)
information that has become public
a tournament in which both professionals and amateurs may play
a clear or unobstructed space or expanse of land or water
where the air is unconfined

open (adjective)	spread out (adjective)
ready or willing to receive favorably
affording unobstructed entrance and exit; not shut or closed
affording free passage or access
(set theory) of an interval that contains neither of its endpoints
open and observable; not secret or hidden
used of mouth or eyes
ready for business
not having been filled
(of textures) full of small openings or gaps
openly straightforward and direct without reserve or secretiveness
not requiring union membership
open to or in view of all
possibly accepting or permitting
without undue constriction as from e.g. tenseness or inhibition
having no protecting cover or enclosure
affording free passage or view
with no protection or shield
accessible to all
not sealed or having been unsealed
not brought to a conclusion; subject to further thought
not defended or capable of being defended

open (verb)	spread out (verb)
make available	set out or stretch in a line, succession, or series
become available	spread out or open from a closed or folded state
make the opening move	move outward
cause to open or to become open	extend in one or more directions
become open	move away from each other
spread out or open from a closed or folded state	turn outward
display the contents of a file or start an application as on a computer	strew or distribute over an area
afford access to
start to operate or function or cause to start operating or functioning
begin or set in action, of meetings, speeches, recitals, etc.
have an opening or passage or outlet