Na2O2 Structure & Characteristics (15 Complete Facts)

Na₂O₂ is the chemical formula of the Sodium peroxide compound. The structure of Na₂O₂ is explained in detail below.

Na₂O₂ is an ionic compound. It is composed of metallic and non-metallic species. The sodium element is a metal and the oxygen atom is non-metal in nature. Thus it produces an ionic compound. It has two sodium and two oxygen atoms in its structure.

In the Na₂O₂ structure, both the sodium atoms donate their one-one electrons to two oxygen atoms. Hence it has a +1 charge on each Na atom. Likewise, two O atoms accept one electron from Na metal and hence it has a -1 charge on each O atom. Let us discuss more details on valence electrons, octet, lone pairs, shape, and more characteristics of Na₂O₂ with detailed facts.

How to draw Na₂O₂ structure?

A detailed explanation drawing the Na₂O₂ structure is described below.

The Na₂O₂ compound shows a hexagonal structure. It is an ionic compound. The 2 O atoms are joined with each other having a single covalent bond in it and forming peroxide (O₂^2-) ions. Each 2 Na⁺ is connected with an ionic bond with each peroxide ion as it donates 1 valence electron to O₂^2- ions.

The stepwise description of the Na₂O₂ structure is given below.

• Na₂O₂ structure has a hexagonal arrangement of 2 Na⁺ and O₂^2- ions in its crystal structure.
• The Na₂O₂ compound crystallizes into a hexagonal space lattice with an O2- (peroxide) ion.
• It lies parallel with the C-axis of the hexagon and each O₂^2- (peroxide) ion is present at the corners of the hexagon and two O₂^2- are inside the hexagon.
• Hence, each O₂^2- (peroxide) ion is surrounded with nine 2 Na⁺ (sodium) cations.
• The two O₂^2- ions are connected with each other by sub-lattice anion molecular bonding with the 2 Na⁺ ions matrix.

Na₂O₂ valence electrons

The outer electron in an atom or element on its outer shell or orbital is known as valence electrons. Let us discuss at Na₂O₂ molecule valence electrons.

The Na₂O₂ compound contains 14 total valence electrons. The sodium atom has 1 valence electron as it comes under the 1st group of the periodic table. The oxygen atom belongs to the 16th periodic table group and has six valence electrons present on it.

The valence electron present in the Na2O2 molecule is explained in the below-given steps.

• Valence electrons of sodium atom of Na₂O₂ is = 1 x 2 (Na) = 2
• Valence electrons on Oxygen atom of Na₂O₂ is = 6 x 2 (O) = 12
• The overall valence electrons on Na₂O₂ compound is = 2 + 12 = 14
• The net electron pairs present on Na₂O₂ molecule is calculated by dividing its valence electrons by 2 = 14 / 2 = 7
• Therefore, the Na₂O₂ molecule has a total of 14 valence electrons and 7 electron pairs present on it.

Na₂O₂ structure lone pairs

The net leftover unshared electron available on an atom or molecule is called lone pair electrons. Na₂O₂ lone pair electron detail explanation is discussed below.

The Na₂O₂ structure has 4 lone pair electrons present in it. It has a net of 14 valence electrons. Six valence electrons are bonding electrons as they form one O –O covalent bond and two Na – O ionic bonds. The remaining 8 unshared valence electrons are 4 lone pair electrons on the Na₂O₂ molecule.

The calculation of Na₂O₂ lone pair electrons is given in the below steps.

• Lone pair electrons on Na₂O₂ is = Valence electrons of Na₂O₂ (V. E) – Number of bonds / 2
• Lone pair electrons on each Na atoms of Na₂O₂ is = 1 (V. E) – 1 / 2 = 0
• Lone pair electrons on each O atoms of Na₂O₂ is = 7 (V. E) – 3 / 2 = 4 / 2 = 2
• Lone pair electrons on Na₂O₂ structure is = 0 (Na) + 2 x 2 (O) = 4
• Hence, the Na₂O₂ structure has four net lone pair electrons on.

Na₂O₂ structure formal charge

The net minimum negative or positive charge on an atom or compound is called a formal charge. Below we are discussing details on the Na₂O₂ structure formal charge.

Formal charge of Na₂O₂ structure is = (valence electrons – non-bonding electrons – ½ bonding electrons)

The detailed calculation and explanation of the Na₂O₂ formal charge are given in the below table.

Na₂O₂ structure shape

The packing and arrangement of atoms of a molecule in a definite manner is called its shape. We are discussing here the details of the Na₂O₂ structure shape.

The Na₂O₂ structure shows a hexagonal shape of its crystal. The VSEPR molecular theory does not apply to Na₂O₂ molecules.

Na₂O₂ hybridization

The process of mixing orbitals of atoms and the formation of a new hybrid orbital with the same energy is known as hybridization. Take a look at the below explanation for Na₂O₂ hybridization.

The Na₂O₂ compound has sp³ hybridization. The two oxygen atoms of the Na₂O₂ molecule are sp³ hybridized. Each oxygen atom has one hybridized orbital and produces one sigma covalent bond between both O atoms. Also, each O atom has 3 lone pair electrons.

Thus each O atom has a -1 charge and is an O₂^-2 anion. This anion gets bonded with two Na⁺ cations with an ionic bond. Here, the mixing and overlapping of 1 ‘s’ and 3 ‘p’ shells or orbitals of two oxygen atoms produce a new ‘sp³’ hybrid orbital having equal energy.

Na₂O₂ structure angle

The gap and angle between any two alternate bonds in a molecule are called the bond angle of that molecule. Let us discuss details on the Na₂O₂ structure bond angle.

The Na₂O₂ structure has 90-degree and 120-degree bond angles. It has a hexagonal crystal structure. Thus the O₂^2- anion is having a 90-degree bond angle and also it has an O – Na – O bond angle is 120 degrees.

Na₂O₂ solubility

The capacity of a solute to dissolve at its maximum in a solvent is called the solubility of that solute or compound. Below we are discussing the solubility of the Na₂O₂ compound.

Na₂O₂ is soluble in the following compounds listed below:

• Cold water
• Hot water
• Dilute acids
• Ethanol

How Na₂O₂ is soluble?

Na₂O₂ is soluble in polar solvents like water. It gets ionized into the water as Na⁺ and O₂^2- ions. Thus the Na⁺ cation attracts the OH^– anion of water and the O₂^2- anion attracts the H⁺ cation of a water molecule. Hence, the hydrogen bond forms between the two opposite ions of Na₂O₂ and H₂O.

The reaction of Na₂O₂ with hot and cold water is given below.

• Sodium peroxide + Hot Water → sodium hydroxide + oxygen
• Na₂O₂ + H₂O → 2 NaOH + O₂
• Sodium peroxide + cold water → sodium hydroxide + hydrogen peroxide
• Na₂O₂ + 2 H₂O → 2 NaOH + H₂O₂

Is Na₂O₂ solid or liquid?

The arrangement of atoms or molecules in a compound with closed or loosely packing forms a solid or a liquid or a gaseous substance. Let us see whether Na₂O₂ is solid or liquid.

Na₂O₂ is a solid compound. It has a crystal structure of hexagonal closed packing. All the 2 Na⁺ and O₂^2- ions are arranged tightly in a regular hexagon. Thus there is a formation of yellow color granular solid crystalline Na₂O₂ compound.

Is Na₂O₂ polar or nonpolar?

The electron distribution and difference in electronegativity of the atoms in the same compound show its polar or non-polar nature. Below we are discussing the Na₂O₂ polar or non-polar nature.

Na₂O₂ is a polar molecule. It already has a +1 charge on the Na atom due to the loss of its 1 electron. It has a -1 charge on the O atom as it accepts 1 electron from the Na atom.

Hence the electron density generated on the more electronegative O atom makes the Na₂O₂ a polar compound.

Is Na₂O₂ acidic or basic?

The acidic and basic compound depends on its loss or gain of protons or electrons with other compounds. Take a look at the detailed discussion on whether Na₂O₂ is acid or base.

Na₂O₂ is a basic compound. As it can react with acids, reducing agents, water, etc., and produce hydrogen peroxide. Thus it acts as a strong base and the reaction is an exothermic reaction while reacting with such compounds.

The reaction of sodium peroxide with hydrochloric acid is given below.

Na₂O₂ + 2 HCl → 2 NaCl + H₂O₂

Is Na₂O₂ electrolyte?

The electrolytic compounds are those which get ionized on adding to water solution and conduct electricity. Let us see whether Na₂O₂ is an electrolyte or not.

Na₂O₂ is an electrolytic compound. On adding Na₂O₂ to water, it can dissolve in water and can dissociate into Na⁺ and O₂^2- ions. These ions can move freely and on the application of an external electric field, it is able to conduct electricity.

Is Na₂O₂ ionic or covalent?

The compounds with ionic bonds are weak and break into ions, while a covalent bond is strong and cannot break. Let us see whether the Na₂O₂ is an ionic or covalent compound.

Na₂O₂ is an ionic compound. It has the composition of metal and non-metal ions. The sodium metal donates its 1 electron to oxygen atoms. Thus, due to the loss and gain of electrons between Na and O atoms, positive charge develops on Na and negative charge develops on O atom.

Due to the combination of 2 Na⁺ cations and O₂^2- anion which is held with the strong electrostatic force of attraction makes a strong ionic bond between 2 Na⁺ and O₂^2- ions, making the Na₂O₂ compound ionic in nature.

Is Na₂O₂ a peroxide?

The compound with two oxygen atoms has a single covalent bond between them with the formula R-O-O-R (R = metal / non-metal atoms). Let us see whether Na₂O₂ is peroxide or not.

Na₂O₂ is peroxide as it is named sodium peroxide. It contains two oxygen atoms that are holding each other with a single covalent bond. Also, the oxygen atom has a -1 oxidation state as peroxides given in the rules of oxidation states. Na₂O₂ is a metal peroxide.

Is Na₂O₂ amphoteric?

Amphoteric compounds show both acidic and basic character as they can react with both acid and base. Let us discuss whether Na₂O₂ is amphoteric or not.

Na₂O₂ is not amphoteric in nature because it is a strong base. It can react with strong acids like hydrochloric acid, sulphuric acid, etc. Thus it forms salt and peroxides.

Is Na₂O₂ stable?

Stable compounds are those which cannot decompose readily and cannot change into other forms of compounds. Take a look below at the description of Na₂O₂ compound is stable or not.

Na₂O₂ is a stable compound. It satisfies the valency and bonding between all the Na and O atoms. Na₂O₂ has a bigger structural size and shows the bonding of 2 Na⁺ ions with 2 O^– ions with the strong electrostatic force of attraction.

The ionic compounds like Na₂O₂ with the strong electrostatic force of attraction are generally stable in nature.

Conclusion:

Na₂O₂ has a hexagonal crystal structure. It has 14 valence electrons and 4 lone pair electrons. It has sp³ hybridization with 90 and 120 degree bond angles. It is soluble in water and other polar solvents. It is an ionic polar electrolyte. It is a stable basic peroxide.

Dr. Shruti Ramteke

Hello everyone, I am Dr. Shruti M Ramteke, I did my Ph.D. in chemistry. I am passionate about writing and like to share my knowledge with others . Feel free to contact me on linkedin