My educated guess should be the 3rd one
A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds. Elements: are pure substances made up of only l type of atom. Atoms of the same element are identical in properties.
Answer:
naoh is called sodium hydroxide,
Explanation:
hope this helps
Answer:
answer: they seek to produce verficiable data.
