25 Facts of Nitrogen Dioxide(NO2) Properties That You Should Know

Nitrogen dioxide is an oxide of nitrogen that is widely found in industrial sewages that possesses toxic environmental effects. Let us learn more in details below.

Nitrogen dioxide is found to be in gaseous form that can cause chronic effects if exposed for longer time. It can be formed from thermal decomposition of metal nitrates or by reaction of nitrogen oxide with molecular oxygen. It is used for creating bleaching agent, as an oxidizer in rocket fuel.

Nitrogen dioxide exists in equilibrium with dinitrogen tetra oxide and is exothermic in nature. Let us study facts like CAS ID, bond length, IUPAC name and many more below.

NO2 IUPAC name

The IUPAC name of NO2 is Nitrogen Dioxide. It has two oxygen atoms connected to nitrogen atom as the central atom.

NO2 chemical formula

The chemical formula of Nitrogen Dioxide is NO2. This suggests that it has one nitrogen atom as the central atom and two oxygen atoms as the connecting atoms.

no2 logo
Bent Shape of NO2, Nitrogen Dioxide molecule

NO2 CAS number

The CAS number of NO2 is 10102-44-0.

NO2 ChemSpider ID

The ChemSpider ID of NO2 is 2297499.

NO2 chemical classification

The chemical classification of NO2 is scripted below.

  • NO2 is a gaseous molecule.
  • NO2 is an oxide of nitrogen.
  • NO2 is brownish in color with chlorine like pungent odor.
  • NO2 has unpaired electron.
  • NO2 has absorption in 400 – 500 nm range of wavelength.

NO2 molar mass

The molar mass of NO2 is 46 g mol-1.

NO2 color

The color of NO2 is brownish-partially reddish. It exists in nature in gaseous form which is brown in color.

NO2 viscosity

The viscosity of NO2 is between 9.34 – 405.92 mPa.s depending on different temperature condition and mole fractions considered.

NO2 molar density

The molar density of NO2 is 1.9 g L-1. It is sufficiently denser than most of the gaseous oxides.

NO2 melting point

The melting point of NO2 is -9.3 0C or 15.3 0F or 263.8 K which is very low due to its less stability.

NO2 boiling point

The boiling point of NO2 is 21.2 0C or 70.1 0F or 294.30 K which is required to undergo phase transformation from liquid to vapor state.

NO2 state at room temperature

The state of NO2 at room temperature is gaseous. This state can established owing to the low melting and boiling point.

NO2 covalent bond

The NO2 molecule has covalent bond existing between N-O. NO2 has partial double bond character due to presence of conjugation.

NO2 covalent radius

The covalent bond radius between nitrogen and oxygen atom in NO2 is 119.7 pm which is an estimated value as the bond has partially double bond character as well.

NO2 electron configurations

Electronic configuration of the respective constituent atoms in a molecule can be evaluated. Let us check the state of each atom in chemical bonding below.

The electronic configuration of N in NO2 is 1s22s22p3 and of O is 1s22s22p4. Only the valence shell electrons i.e., in 2s and 2p orbitals of O and N take part in bond formation.

NO2 oxidation state

The oxidation state of NO2 is overall zero as it is a neutral molecule. The oxidation state of N is +4 formed by transferring four electrons to two O atoms and oxidation state of each O atom is -2.

NO2 acidity/alkaline

NO2 shows acidity character due to being an acidic oxide as it reacts with water molecules to form acidic solutions.

Is NO2 odorless?

NO2 is not odorless as it has a chlorine like smell that possesses an irritating odor.

Is NO2 paramagnetic?

Paramagnetism is a phenomenon shown due to the presence of unpaired electron in presence of external magnetic field. Let us discuss in details below.

NO2 is a paramagnetic material. It is due to the presence of unpaired electron on N atom. This unpaired electron can align itself to the external field applied and can show magnetism. As such, it gives rise to paramagnetism that can show permanent magnetism when field is applied.

NO2 hydrates

NO2 does not form hydrates but during complex reaction formation, it can form hydrates in the coordination sphere along with transition metal as the central atom.

NO2 crystal structure

The crystal structure of NO2 is monoclinic with lattice parameters of sides a b c and angles of the lattice system α = γ = 90o ≠ β.

NO2 polarity and conductivity

  • The exact polarity of NO2 is not yet identified and measured.
  • The conductivity of NO2 which exists in equilibrium with N2O4 is found to be 1.3 * 10-12 k ohm-1 cm-1.

NO2 reaction with acid

NO2 is an acidic oxide but it does react with HCl gas to produce chlorine gas and nitrous oxide as shown in the example.

  • NO2 + 2HCl -> NO + Cl2 +H2O

NO2 reaction with base

NO2 is acidic in nature so it can react with bases like NaOH, O3 etc. as shown in the given examples.

  • 2NO2 + 2NaOH -> NaNO2 + NaNO3 + H2O
  • NO2 + O3 -> O2 + NO3                                                                                                                    

NO2 reaction with oxide

NO2 reacts with other oxides like that of nitrogen oxides to form dinitrogen trioxide as shown in example.

  • NO2 + NO -> N2O3
  • NO2 + O3 -> O2 + NO                                                                                                                   

NO2 reaction with metal

NO2 reacts with metal to form few complexes as shown below in the given example.

  • 6NO2 + Co -> [Co(NO2)]3-

Conclusion

NO2 is an oxide of nitrogen that exists in equilibrium with N2O4 and is used for creating bleaching agents. It can reach to living beings through stratosphere. It is brownish in color.