conservation of energy vs first law of thermodynamics

conservation of energy and first law of thermodynamics both are nouns.

Word	Noun	Adjective	Verb	Adverb
conservation of energy	Yes	No	No	No
first law of thermodynamics	Yes	No	No	No

As nouns, conservation of energy and first law of thermodynamics are synonyms defined as:

conservation of energy and first law of thermodynamics: the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes

Other synonyms of conservation of energy include law of conservation of energy.

conservation of energy (noun)	first law of thermodynamics (noun)
the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes	the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes