Question

Which periodic group forms +1 ; +2 and -1 ions?

Answer 1

Hint: The charge on a ion indicates the no. of electrons that is lost or gained to attain the stable electronic configuration of Noble gas or the inert gas configuration. If an electron is lost the ions have positive charge and if an electron is gained it has negative charge.

Complete Step By Step Answer:
Here we are asked which periodic group has the charge of +1,+2 and -1. The group I of the periodic table also known as the alkali metals, belong to the s-block of the periodic table. It has the outer electronic configuration of $n{s}^1$ i.e. it has to lose one electron from its valence shell to attain the inert gas configuration. Hence the charge of it is +1.
The group II of the periodic table are known as alkaline earth metals They also belong to the s-block of the periodic table. The outer electronic configuration is $n{s}^2$ i.e. they have to lose these two electrons to attain the stable electronic configuration. The loss of electrons leads to the formation of +2 charge on the element.
-1 charge is attained when an element accepts one electron into its valence shell. This is commonly found in the group XVII of the periodic table, known as the Halogen family. They have the electronic configuration of $n{s}^{2}n{p}^5$. Hence accepting one electron will fill the p orbital with 6 electrons and make the element stable with 8 electrons in the outermost shell.
Hence +1,+2 and -1 charge is shown by Group I, Group II and Group XVII of the periodic table.

Note:
The elements that belong to group I are Helium, Lithium, Sodium, Potassium, Rubidium, Caesium and Francium. They are known as alkali metals as they form hydroxides on reaction with water, which are strongly alkaline in nature. Group II is known as Alkaline earth metals and consists of Beryllium, Magnesium, Calcium, Strontium, Barium, Radium. Group XVII is known as Halogen and are mainly gases, consisting of Fluorine, Chlorine, Bromine, Iodine.