Clo4- lewis structure,Characteristics:13 Facts You Should Know

Clo4- lewis structure and other important characteristics are explained in this article.

Perchlorate,ClO4 is a monovalent anion which consists of chlorine atom attached with four oxygen atoms. Its molecular weight is 99.45g/mol and is a good oxidiser.

Facts about Perchlorate,ClO4

Perchlorate,ClO4 is an inorganic anion which is monovalent. It combines with other metals to form stable salts like ammonium chlorate, sodium chlorate, potassium chlorate, perchloric acid. Its most simple salt is perchloric acid. There is mainly man- made and natural perchlorates.

Sodium perchlorate can be formed through oxidation reaction of aqueous solution of sodium chlorate. It has been observed that lightening in presence of chlorine also produces perchlorates. It exists as a white crystalline solid or colourless liquid which get fire on exposure to heat.

Perchlorates discharge sources are mainly disinfectant, bleaching agents, rocket propellants, etc. This discharge cause contamination of water. This can be only removed by high pressure water washout. It is toxic to thyroid gland. It is mainly used in fireworks, control static electricity in food packing, oxidiser in solid propellants, fireworks, air bag initiators for vehicles.

Lewis Structure of Perchlorate,ClO4

The Lewis structure of perchlorate is drawn through the following steps.

  • The atoms present in perchlorate is one chlorine with four oxygen atoms. There is an excess electron too. So let’s calculate it’s total number of valence electrons present. It is 7+6X4+1 = 32.
  • In the next step write chlorine as central atom with four oxygen around it. Form a single bond between each chlorine and oxygen. For bond formation eight electrons took. The remaining electrons are distributed equally around all the oxygen atoms in accordance with octet rule.
clo4- lewis structure
Lewis structure of ClO4
  • When we consider the formal charges of the above Lewis structure it is found to be 3 and -1 for chlorine and oxygen respectively. To get a stable structure it’s formal charge has to be lowered.
  • Therefore three oxygen atoms shares it’s electrons with chlorine to make another bond. There by reducing its formal charge to obtain a stable Lewis structure for perchlorate.
Stable Lewis Structure of ClO4 –

Resonance in Perchlorate, ClO4

Perchlorate ion has resonance structures due to the movement of lone pair of electrons associated with oxygen atom. This give rise to four structures to perchlorate ion. All its properties and electronic arrangement is retained during this process. It is just the movement of the negative charge associated with the oxygen atom.

Resonance in ClO4

Octet Rule in Perchlorate,ClO4

In perchlorate ion there is one chlorine with four oxygen atoms. From its stable Lewis structure we can understand whether it obeys octet or not. Looking on all the oxygen atoms they have eight electrons in its outer shell after bond formation. So they obey octet rule. In case of chlorine it has more than eight that is it is found to be hypervalent atom and it is stable.

Shape and Angle of Perchlorate,ClO4

The shape of molecules are usually found out through VSEPR theory. On the basis of this theory we can predict the geometry of perchlorate ion. It is AX4 type molecule with no lone pairs in central atom. Here chlorine is attached with four oxygen. Therefore its steric number is four.

Therefore it can have either tetrahedral shape if there is no lone pair with central atom, or any other shape depending upon the number of lone pair. Here there is no lone pair with chlorine it has tetrahedral shape with a bond angle of 109.50 between the bonds. The bond length of chlorine oxygen bond is almost 1.44 pm.

Shape and Bond Angle in ClO4

Formal charge in Perchlorate,ClO4

The formal charge of perchlorate is calculated through its most stable Lewis structure.

Formal charge of an atom = (Valence electrons – No. of non- bonded

                                                electrons – No. of bonds made)
The formal charge of chlorine = 7-0-7 = 0
The formal charge of oxygen = 6-4-2 = 0

Therefore the formal charge of perchlorate of zero.

Valence electrons in Perchlorate,ClO4

The total number of valence electrons involved in perchlorate ion is 32.

Lone pair in Perchlorate,ClO4

Lone pair of electrons can be found with perchlorate ion. Central atom chlorine doesn’t have any one. But the surrounded oxygen atom has. Three of the oxygen has two pairs each and one has three pairs. So in total there is nine lone pairs are present in perchlorate ion which is associated with oxygen atom.

Lone Pairs in ClO4

Hybridisation in Perchlorate,ClO4

The hybridisation of perchlorate molecule can be found out through the following equation.

          Hybridisation = ½[ valence electrons – monovalent atom – cationic 

                                     Charge + anionic charge]

Hybridisation = ½[7-0-0+1] = 8/2 = 4

Perchlorate ion follows sp3 hybridization. So it has tetrahedral geometry.

Solubility of  Perchlorate,ClO4

Perchlorate ion is highly soluble in water. This is due to the presence of negative charge around it. Water is a polar molecule with H+ and OH ions. When it dissolves in water it will combines with H+ ion to form perchloric acid. Due to non- polar nature of certain organic solvents it is not found soluble in them.

Is Perchlorate,ClO4 Ionic or not ?

Perchlorate ion is an anion. That is a negative charge is associated with the molecule. So it is ionic in nature.

Is Perchlorate,ClO4 Polar or not ?

Perchlorate is a non- polar molecule. There is an electronegativity difference can be seen in between the atoms. But the molecule is symmetrical in shape. So the dipole moment of each bond got cancelled. Therefore it will remain as a non- polar molecule.

Is Perchlorate,ClO4 Acidic or not ?

Some of the stable perchlorates are found to be acidic in nature. But some are neutral. Perchloric acid, ammonium perchlorate are acids but the other ones like sodium perchlorate, potassium perchlorate are neither acid not base. They are neutral substances.

Is Perchlorate ion, ClO4 Tetrahedral or Linear ?

Perchlorate is a molecule with tetrahedral shape. It follows sp3 hybridisation with zero lone pairs around the central atom.

Tetrahedral Shape of ClO4


Perchlorate, ClO4- is an inorganic anion which is in sp3 hybridised state with tetrahedral geometry, 109.50 bond angle. Due to its symmetrical shape it is non- polar with good miscible nature in water. Some of its stable compounds are neutral and some are acidic in nature. Its Lewis dot structure is drawn by taking its 32 valence electrons.

Aparna Dev

Hi... I am Aparna Dev, a chemistry postgraduate with a good understanding of chemistry concepts. I am working in Kerala Minerals and Metals Limited Kollam with experience in the development of electrocatalysts as a part of post graduate thesis. Let's connect through LinkedIn-

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