I have read the Chem.SE question about the difference between 'compound', 'mixture', 'element' and 'molecule', but I would like to know the precise definitions for more terms (see below). From the article, these are the definitions:
Elements are classes of atoms. Atoms of the same element are similar (if not identical) in their physical and chemical properties (but be aware of Isotopes which are physical variations among atoms of the same element).
Molecules are a group of atoms covalently bonded to each other.
Compounds are made up of two or more elements. Compound is often used interchangeably with the word substance.
Mixtures are collectives of different molecules or atoms.
How are compounds substances? Isn't 'substances' a general term for any chemical thing?
These are the terms that I would like definitions for:
- chemical species
- substance
- particle
- atom/isotope
- salt
I am rather confused about these terms, because my tutor uses particles and molecules (and elements) as if they were the same thing. As for the rest, I want to know how to distinguish between general (such as chemical species, substance) and specific terms (such as particle, atom, isotope, salt).