Answer:
4- radioactive isotopes
Explanation:
I don't remember exactly but this question was on the regents
A cation is a positively charged ion.
An anion is a negatively charged ion.
If it's neutral, it's just an ion.
Transferring or sharing electrons between atoms forms a covalent bond.<span> Covalent
bonding is when atoms share electrons. It is a chemical bond that involves the
sharing of electron pairs. These pairs are called bonding pairs. Examples of
compounds that has covalent bonds are CO2, organic compounds, lipids and
proteins.</span>
What of the gasses is N and the flame changes it's color from Orange to blue