Describe the formation of an ion from a metal and a nonmetal in terms of the octect rule.

Elements classified as metals tend to lose electrons. Except for hydrogen, all other metallic elements lose their outside electrons so that the next inner shell is complete, often with an octet(elements 3 & 4 lose their outside electrons to leave the next inner shell full but that shell (n = 1) is full with only two electrons). For non-metals, the tendency is to gain electrons to make the outside shell an octet. Repost if this isn't clear.

The octet rule states that atoms tend to gain, lose, or share electrons in order to achieve a stable electron configuration with a full outermost energy level of eight electrons, known as an octet.

When a metal and a nonmetal react with each other, the metal tends to lose electrons and the nonmetal tends to gain electrons. This allows the metal to achieve a stable electron configuration by losing enough electrons to have a full inner shell, while the nonmetal achieves a stable electron configuration by gaining enough electrons to have a full outermost energy level.

Let's take sodium (Na) and chlorine (Cl) as an example. Sodium is a metal and chlorine is a nonmetal. Sodium has one electron in its outermost energy level and chlorine has seven electrons in its outermost energy level.

In order for sodium to achieve a stable electron configuration, it needs to lose one electron. By losing this one electron, sodium now has a complete inner shell. The resulting sodium ion, Na+, has a positive charge because it now has one more proton than electrons.

On the other hand, chlorine needs to gain one electron in order to achieve a stable electron configuration with a full outermost energy level. By gaining this one electron, chlorine now has a complete octet. The resulting chloride ion, Cl-, has a negative charge because it now has one extra electron compared to its number of protons.

In summary, the formation of an ion from a metal and a nonmetal follows the octet rule. The metal tends to lose electrons to achieve a stable electron configuration, while the nonmetal tends to gain electrons to achieve a stable electron configuration with a full outermost energy level.