Write the uses of Ions .

This is what they are: An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

This is their purpose: Once they reach our bloodstream, negative ions are believed to produce biochemical reactions that increase levels of the mood chemical serotonin, helping to alleviate depression, relieve stress, and boost our daytime energy.

Explanation:

i believe the answer is a.

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements