Answer:
substance
Explanation:
A mixture is when two or more <u>different</u> atoms/molecules are together, but not joined.
A substance is when the <u>same </u>atom/molecule is in a group together.
In this example, it is a substance because it is comprised of the same molecule not joined all together. If you wanted a mixture, other colored atoms/molecule (e.g. add green atoms) would change it to this property.
That is correct c
Explanation
Boiling Water is a physical change. When water gets to a certain temperature, it's boiling point starts.
The formal charge of H = +1, because F in compounds can have only -1.
