Question

How do you know the charge of an element from the periodic table?

Answer 1

Periodic table:

• The periodic table is a tabular arrangement of the chemical elements in the increasing order of atomic number.
• A period is the collection of elements that are arranged in a horizontal row of the periodic table.
• A group is the collection of elements that are arranged in a vertical row of the periodic table.

Charge of an element from the periodic table:

• Atoms can either gain or lose valence electrons to become more stable.
• Metals will lose electrons and form positively charged ions and nonmetallic elements will gain electrons and form negatively charged ions.
• The position of an element on the periodic table tells about the type of ions it will form, with the elements on the right forming anions (negative charge) and those further to the left forming cations (positive charge).
• The first two groups have elements with only one or two electrons in their outer shells, groups 1 $\left({\mathrm{ns}}^1\right)$and 2 $\left({\mathrm{ns}}^2\right)$respectively. These elements will lose electrons to gain a charge of +1 or +2.
• The elements in the 13th$\left({\mathrm{ns}}^2{\mathrm{np}}^1\right)$ group have three electrons in the outermost shell, so these elements will lose electrons to gain a charge of +3.
• In the 14th group$\left({\mathrm{ns}}^2{\mathrm{np}}^2\right)$, there are four electrons in the outermost shell, so these elements will lose or gain electrons to gain a charge of +4 or -4 respectively.
• The 15th group$\left({\mathrm{ns}}^2{\mathrm{np}}^3\right)$ elements have 5 electrons in their outermost shell, so they will gain 3 electrons to make an octet configuration and will gain a charge of -3.
• The 16th group$\left({\mathrm{ns}}^2{\mathrm{np}}^4\right)$ elements have 6 electrons in their outermost shell, so they will gain 2 electrons to make an octet configuration and will gain a charge of -2.
• The 17th group$\left({\mathrm{ns}}^2{\mathrm{np}}^5\right)$ elements have 7 electrons in their outermost shell, so they will gain 1 electron to make an octet configuration and will gain a charge of -1.