Question

Learning Goal: To become familiar with the octet rule and to use it to determine the charges of ions. Noble gases are especially stable because their valence shells are full. This is referred to as having an octet, because most valence shells contain eight electrons. Other elements will gain or lose electrons to achieve an octet and become an ion. A positively charged ion has lost electrons and is called a cation whereas a negatively charged ion has gained electrons and is called an anion. Nonmetals tend to gain electrons to form anions Metals tend to lose electrons to form cations.

Answer 1

Step-by-step explanation:

It is true that when a neutral atom tends to lose an electron then it forms a positively charged ion called cation. And, when a neutral atom tends to gain an electron then it forms a negatively charged ion called anion.

For example, the atomic mass of magnesium is 12 and its electronic configuration is
`1s^(2)2s^(2)2p^(6)3s^(2)`.

So, in order to attain noble gas configuration it will lose its 2 valence electrons. Therefore, it will form
`Mg^(2+)` ion.

And, atomic number of chlorine is 17 and its electronic configuration is
`1s^(2)2s^(2)2p^(6)3s^(2)3p^(5)`. To attain noble gas configuration it will readily accept an electron from a donor atom.

Hence, it will form
`Cl^(-)` ion.