Iodic Acid Formula: Formation and Lewis Structure

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Iodic acid HIO₃ can be obtained as a white solid. It dissolves in water very well but it also exists in pure state as opposed to chloric acid or bromic acid. Per-Iodic acid is HIO₄. Iodic acid contains iodine in the oxidation state +5 and is one of the most stable oxyacids of the halogens in its pure state.

Table of Content

Formation of ionic acid
Lewis structure of ionic acid
Parts of Human Tooth
Formation of Dental Lamina
What are Diphyodont and Polyphyodont?
Things to Remember
Sample Questions

Key Takeaways: Iodic acid formula, Iodic acid, HIO₃, Oxidation state, Iodine

Formation of ionic acid

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Oxidation of I₂ to HIO₃ by concentric nitric acid i.e. HNO₃

First we heat nitric acid and we get water, nitrogen dioxide and nascent oxygen.

2HNO₃ → H₂O +2NO₂ + [O]

In the second step, iodine is reacting with nascent oxygen and gets iodine pentoxide.

I₂ + 5[O] → I₂O₅

In third step, iodine pentoxide reacts with water and gets iodic acid

I₂O₅ + H₂O → 2HIO₃

Combine all these above reaction,

2HNO₃ → H₂O +2NO₂ + [O] × 5

I₂ + 5[O] → I₂O₅

I₂O₅ + H₂O → 2HIO₃

I₂ + 10HNO₃ → 4 H₂O + 10 NO₂ + 2HIO₃

(Note- In red color, same reactant and product will be cancel, One H₂O is canceled out from 5 H₂O)

Oxidation of I₂ to HIO₃ by chlorine Cl₂

Iodine ( I₂ ) is oxidizing with chlorine (Cl₂ ) with water (H₂O) give iodic acid (HIO₃ ) and hydrochloric acid (HCl)

I₂ + 6 H₂O + 5 Cl₂ → 2 HIO₃ + 10 HCl

Oxidizing agent

Redox reaction

Lewis structure of ionic acid

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To draw the lewis structure of HIO₃, we need to realize that this is an acid. Whenever the hydrogen atom is in front that means we draw the lewis structure and put one of the oxygen outside. So , iodine in the center then oxygen and put the hydrogen outside. In HIO₃ there are 26 valence electrons. Each atom has eight electrons and hydrogen has two electrons.

Lewis structure of ionic acid

Lewis electron dot structure

Chemical bonding and molecular structure

Properties of Iodic Acid

Given below are the properties of iodic acid formula:

The chemical formula of iodic acid is HIO3.
The molar mass is 175.91 g/mol.
It looks like white solid and the density of iodic acid is 4.42 g/cm3.
The melting point is 110ºC.
It is corrosive in nature and non flammable and is strongly oxidizing in acidic solution and less in basic solution.
The acid dissociation constant or acidity constant ( PKa ) is 0.75.

PKa acid strength

mole

Uses of Iodic Acid Formula

It is used as a strong acid in analytical chemistry. It is used in the salt industry to increase the iodine content in salt.

Points to Remember

The chemical formula of iodic acid is HIO3
The iodic acid is a part of oxyacids
The oxidation state of iodic acid is +5
The iodic acid can be prepared by oxidizing iodine with strong oxidizers nitric acid, chlorine, chloric acid and hydrogen peroxide
The main application of iodic acid in salt industry

Sample Questions

Ques - Calculate the molar mass of iodic acid. (2 marks)

Ans: HIO3

(1× H) = 1×1 = 1

(1 × I) = 1×126.90 = 126.90

(3×O) = 3× 16 = 48

Molar mass = 1 + 126.90 + 48 = 175.9 g

Ques- Calculate the percent iodine in iodic acid. (2 marks)

Ans: Formula of iodic acid – HIO3

Molar mass = 175.9 g

Mass of iodine = 126.90 g

% Iodine = (Mass of iodine/ molar mass) × 100

% Iodine = (126.90/ 175.9) × 100

% Iodine = 72.14 %

Ques- Calculate the oxidation number in HIO₃ (2 marks)

Ans: The oxidation number of H is +1

The oxidation number of O is -2

H+1 Ix O3-2

(+1) + x + 3(-2) = 0

1 + x – 6 = 0

x = 5

Ques- Calculate the oxidation number in HIO₄ (2 marks)

Ans: The oxidation number of H is +1

The oxidation number of O is -2

H+1 Ix O4-2

(+1) + x + 4(-2) = 0

1 + x – 8 = 0

x = 7

Ques- Calculate the valence electrons of iodic acid. (2 marks)

Ans: Valence electrons depends upon the group number of molecule in the periodic table

Iodic acid HIO3

Hydrogen belongs to group one, hence valence electron of hydrogen is 1

Similarly, valence electron of oxygen is 6 and iodine is 7

Valence electron = 1 + 7 + 3(6) = 26

Ques- Calculate the formal charge of iodine from the following lewis structure of iodic acid. (3 marks)

Ans:

Valence electron = 7

Non bonding valence electron = 2

Bonding electron = 6

Formal charge = Valence electron – Non bonding valence electron – (Bonding electron)/2

I = 7 – 2 – 6/2

I = 2

Ques- Calculate the formal charge of the first oxygen atom from the following lewis structure of iodic acid. (3 marks)

Ans: Valence electron = 6

Non bonding valence electron = 6

Bonding electron = 2

Formal charge = Valence electron – Non bonding valence electron – (Bonding electron)/2

O = 6 – 6 – 2/2

O = -1

Ques- How is the iodic acid prepared ? Explain with reaction. (5 marks)

Ans: The iodic acid can be prepared by oxidizing iodine with strong oxidizers nitric acid, chlorine, chloric acid and hydrogen peroxide

Oxidation of I2 to HIO3 by concentric nitric acid i.e. HNO3

Step 1- Heat nitric acid and we get water, nitrogen dioxide and nascent oxygen.

2HNO3 → H2O +2NO2 + [O]

Step 2- Iodine is reacting with nascent oxygen and gets iodine pentoxide.

I2 + 5[O] → I2O5

Step 3- Iodine pentoxide reacts with water and gets iodic acid

I2O5 + H2O → 2HIO3

Combine all these above reaction,

2HNO3 → H2O +2NO2 + [O] × 5

I2 + 5[O] → I2O5

I2O5 + H2O → 2HIO3

I2 + 10 HNO3 → 4 H2O + 10 NO2 + 2HIO3

Ques– Explain iodic acid by lewis structure. Draw the structure also. (2 marks)

Ans: Whenever the hydrogen atom in front that means draw the lewis structure and put one of the oxygen outside. So , iodine in the center then oxygen and put the hydrogen outside. In HIO3 there are 26 valence electrons. Each atom has eight electrons and hydrogen has two electrons.

Ques– What are the properties and uses of iodic acid? (5 marks)

Ans: Properties of iodic acid:

The chemical formula of iodic acid is HIO₃.
The molar mass is 175.91 g/mol. It looks like white solid.
The density of iodic acid is 4.42 g/cm3, solid.
The melting point is 110ËÂ\(\Box\)C. It is corrosive in nature and non flammable.
Strongly oxidizing in acidic solution and less in basic solution.

Ques- What are the uses of iodic acid? (2 marks)

Ans. Uses of iodic acid are:

It is used as a strong acid in analytical chemistry.
It is used in the salt industry to increase the iodine content in salt.

Also Read:

Chemistry	Cobalt	Metals and Non-Metals
Covalent Bonds	Precipitation Titration	Halogen
Types of Titration	Redox Titration	Nickel Sulfate
Amorphous and Crystalline Solids	Balanced Chemical Equation	Sulfuric Acid
Displacement Reaction	Decomposition Reaction	Oxidation and Reduction

Iodic Acid Formula: Formation and Lewis Structure

Formation of ionic acid

Lewis structure of ionic acid

Properties of Iodic Acid

Uses of Iodic Acid Formula

Points to Remember

Sample Questions

CBSE CLASS XII Related Questions

1.
Following reaction takes place in one step:

\(2A + B \rightarrow 2C\)

How will the rate of above reaction change if the volume of the reaction vessel is decreased to one third of its original volume? Will there be any change in the order of reaction with the reduced volume?

2.
Explain the Finkelstein reaction.

3.
(a) Write two structural differences between DNA and RNA.
(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.
(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

4.
The chelating ligand used for the treatment of lead poisoning is :

5.
An organic compound (X) has the molecular formula \(C_5H_{10}O\). Draw structures for (X) if it:
(I) does not give Tollen's test but gives a positive iodoform test.
(II) does not give Tollen's test and iodoform test but undergoes Aldol condensation.
(III) undergoes Cannizzaro's reaction.

Comments

SUBSCRIBE TO OUR NEWS LETTER

Iodic Acid Formula: Formation and Lewis Structure

Formation of ionic acid

Lewis structure of ionic acid

Properties of Iodic Acid

Uses of Iodic Acid Formula

Points to Remember

Sample Questions

CBSE CLASS XII Related Questions

1.Following reaction takes place in one step:\(2A + B \rightarrow 2C\)How will the rate of above reaction change if the volume of the reaction vessel is decreased to one third of its original volume? Will there be any change in the order of reaction with the reduced volume?

2.Explain the Finkelstein reaction.

3.(a) Write two structural differences between DNA and RNA.(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

4.The chelating ligand used for the treatment of lead poisoning is :

5.An organic compound (X) has the molecular formula \(C_5H_{10}O\). Draw structures for (X) if it: (I) does not give Tollen's test but gives a positive iodoform test. (II) does not give Tollen's test and iodoform test but undergoes Aldol condensation. (III) undergoes Cannizzaro's reaction.

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
Following reaction takes place in one step:

\(2A + B \rightarrow 2C\)

How will the rate of above reaction change if the volume of the reaction vessel is decreased to one third of its original volume? Will there be any change in the order of reaction with the reduced volume?

2.
Explain the Finkelstein reaction.

3.
(a) Write two structural differences between DNA and RNA.
(b) Which component of starch is a branched chain polymer of \( \alpha \)-D-(+)-glucose ? Write its one characteristic feature.
(c) Which types of bonds hold the polypeptide chains in fibrous proteins ?

4.
The chelating ligand used for the treatment of lead poisoning is :

5.
An organic compound (X) has the molecular formula \(C_5H_{10}O\). Draw structures for (X) if it:
(I) does not give Tollen's test but gives a positive iodoform test.
(II) does not give Tollen's test and iodoform test but undergoes Aldol condensation.
(III) undergoes Cannizzaro's reaction.