Question

What is wrong with Lewis dot structure for $I{{O}^{-}}$ ?

A.The bond between $I$ and $O$ should be represented with a single line.
B.The negative symbol should be on the inside of the brackets
C.Oxygen is not satisfied according to the octet rule
D.These are not enough electrons

Answer 1

In this problem, we first briefly talk about the Lewis dot structure. And how a lewis dot structure is drawn to a compound. We also speak of the regulations that to be followed even as drawing the Lewis dot structure of a compound. Then we discover the error within the given lewis dot structure.

Complete step by step answer:

Lewis methods are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist inside the molecule. A Lewis shape can be drawn for any covalently bonded molecule, in addition to coordination compounds. Lewis' method extends the concept of the electron dot diagram with the aid of adding strains among atoms to represent shared pairs in a chemical bond.
Lewis structures display each atom and its function within the structure of the molecule using its chemical symbol. Lines are drawn among atoms which can be bonded to each other. Excess electrons that shape lone pairs are represented as pairs of dots, and are placed next to the atoms. Although essential group factors of the second duration and past typically react by way of gaining, dropping, or sharing electrons until they've carried out a valence shell electron configuration with a complete octet of (eight) electrons, hydrogen (H) can best shape bonds which share simply electrons.
The general variety of electrons represented in a Lewis shape is the same as the sum of the numbers of valence electrons on each character atom. Non-valence electrons aren't represented in Lewis systems. Once the total wide variety of available electrons has been decided, electrons have to be located into the structure consistent with those steps:
The atoms are first related by unmarried bonds. If t is the total variety of electrons and n the variety of unmarried bonds, t-2n electrons continue to be to be placed. These should be placed as lone pairs: one pair of dots for every pair of electrons available. Lone pairs must begin to be positioned on outer atoms (other than hydrogen) until each outer atom has 8 electrons in bonding pairs and lone pairs; greater lone pairs can also then be located on the valuable atom. When in doubt, lone pairs must be placed on greater electronegative atoms first.
Once all lone pairs are placed, atoms (especially the crucial atoms) may not have an octet of electrons. In this case, the atoms have to shape a double bond; a lone pair of electrons is moved to form a second bond between the 2 atoms. As the bonding pair is shared among the two atoms, the atom that firstly had the lone pair nevertheless has an octet; the opposite atom now has more electrons in its valence shell.
Lewis structures for polyatomic ions can be drawn through the same technique. When counting electrons, bad ions should have greater electrons positioned on their Lewis structures; wonderful ions should have fewer electrons than an uncharged molecule. When the Lewis shape of an ion is written, the complete structure is positioned in brackets, and the fee is written as a superscript on the top proper, outside the brackets.
Now, let us see the given Lewis dot structure,

In a Lewis dot structure, a single bond must be drawn from the central atom to the opposite atom for every shared pair of electron
Net charge at the compound have to constantly be outside the brackets
Number of electrons to be had with oxygen is eight which satisfies oxygen consistent with the octet rule.
Total number of electrons on $I{{O}^{-}}$ $=7+6+1=6$ which is equal to that in the Lewis structure.
Hence, option A is the correct answer.

Note:
A trick is to count up valence electrons, then count up the number of electrons needed to complete the octet rule (or with hydrogen just 2 electrons), then take the difference of these two numbers and the answer is the number of electrons that make up the bonds. The rest of the electrons just go to fill all the other atoms' octets.