Which of the definitions below is best for the word molecule? Atoms of different elements chemically joined together More than one atom chemically joined together A type of compound More than one atom of the same type chemically joined together A group of atoms together

More than one atom of the same type chemically joined together

Explanation:

An atom is the smallest unit of any matter which may or may not have independent existence. Example: Argon (Ar) is an element which exist as Ar atom only.

Molecule is the smallest unit of any matter which always have independent existence. For example: Hydrogen (H) is an element which can exist in nature as molecule only.

Atoms of different elements chemically joined together is called as a compound. Example: is a compound formed by chemical combination of hydrogen (H) and oxygen (O) atom.

0.0038 M

Explanation:

Hardness of the water is generally due to the presence of in water.

At equivalence point

Moles of = Moles of EDTA

Considering

Given  that:

So,