Nitromethane (CH3NO2) is the simplest organic compound that has nitro as a functional group. For this reason, the molecule is commonly referred to as an explosive, an important explosive compound.
To make it clearer, nitromethane is widely known as a nitro booster used in drag racing engines. It is a colorless liquid with a strong pungent odor that produces fumes of nitrogen oxides when it decomposes violently when overheated. In addition, the liquid is oily and flammable, making it a good choice as a fuel.
Because it is highly toxic to the human body, nitromethane can irritate the skin and affect the central nervous system, making it an important human carcinogen to study.
Nitromethane is a nitroalkane formed when a hydrogen is replaced with a nitro group. Using a laboratory method, nitromethane is produced when sodium chloroacetate reacts with sodium nitrite in an aqueous state.
The reaction as follows:
ClCH2COONa + NaNO2 + H2O ——–> CH3NO2 + NaCl + NaHCO3
The Lewis Structure of Nitromethane (CH3NO2)
To get started with the Lewis structure of nitromethane, it is crucial to first examine the individual atoms involved. The atomic number of carbon is 6, making its electron configuration 1s2 2s2 2p2.
Since we know that the p-shell needs 6 valence electrons to complete its octet, 4 more valence electrons are needed. Because of this, the total number of valence electrons in a carbon atom is 4.
Well, for the hydrogen atom, its atomic number is 1, making its electron configuration 1s1. Since the s shell needs 2 electrons to complete its octet, 1 electron is needed. Because of this, the total number of valence electrons for hydrogen is 1.
In the case of the nitrogen atom, its atomic number is 7 and its electron configuration is 1s2 2s2 2p3. Since the p-shell needs 6 valence electrons, it is missing 5 electrons. Because of this, the valence electrons in the nitrogen atom are 5.
Finally, in the case of oxygen, its atomic number is 8, so its electron configuration is 1s2 2s2 2p4.
Here it is important to know that the valence electrons are also those that are present in the highest main energy level, that is s and p for the oxygen atom. The total number of valence electrons in oxygen is 6.
Below is the picture of Lewis structure of atom of carbon, nitrogen and oxygen.
Steps to Draw the Lewis Structure of Nitromethane (CH3NO2)
Step 1:Find the total number of valence electrons present in a single molecule of nitromethane (CH3NO2).:
It's 24 because 4 are from the carbon atom, 1 from each hydrogen atom, 5 from the nitrogen atom, and 6 from each oxygen atom.
step 2:Find out how many more valence electrons are needed for a single molecule of nitromethane (CH3NO2).:
There are 14 because 4 are needed for the carbon atom, 1 for each hydrogen atom, 3 for the nitrogen atom, and 2 for each oxygen atom.
step 3:Find the central atom in a nitromethane molecule (CH3NO2):
The molecular formula shows that the hydrogen atoms are attached to the carbon atom while the oxygen atoms are attached to the nitrogen atom.
With this information, it is clear that there are two central atoms that are linked by a single bond.
Level 4:Look for the type of bond formation between participating atoms in a nitromethane (CH3NO2) molecule:
It is important to understand that we are talking about nitromethane and not methyl nitrite. Confusion can arise as the molecular formula of the compounds is the same.
But it is important to understand how each of the atoms involved forms which type of bond.
Methyl nitrite has an oxygen atom bonded to carbon, which nitromethane does not. Each atom involved forms a covalent single bond, while a covalent double bond forms between nitrogen and an oxygen atom.
step 5:Now put all the steps together and draw the Lewis structure of the nitromethane.:
Geometria Molecular do Nitrometano
From the Lewis structure we know two central atoms in a single nitromethane molecule. Thus, there are two molecular geometries for separate units of -CH3 and -NO2.
The bond angle between the hydrogen-carbon-hydrogen atoms is 109.5° and that of the carbon-nitrogen-oxygen atom is 120°.
It is important to understand here that the hydrogen-carbon-nitrogen bond is linear; H. 180°, so this discussion will not have much content.
The molecular geometry of nitromethane (CH3NO2) can be studied using the valence shell electron pair repulsion theory (VSEPR). He says that the -CH3 end is tetrahedral while the -NO2 end is trigonal planar due to the bond angle they form.
The VSEPR chart is attached below.
It may interest you that even after the presence of lone pairs of electrons, a distortion of the ideal shape and bond angle occurs.
This is because the lone pairs of electrons are present at the rate at which they would normally cancel each other out, neutralizing the effect.
Hybridization in nitromethane (CH3NO2)
From the molecular geometry it can be seen that the nitromethane molecule (CH3NO2) follows ideal conditions whereit is clear that the carbon atom is sp3 hybridized while the nitrogen atom is sp2 hybridized.
In the case of the carbon atom, the s and 3p orbitals of the same shell mix and overlap to create four new orbitals of similar energy. The newly created orbitals have 25% s orbital properties and 75% p orbital properties.
Whereas in the case of the nitrogen atom, an s orbital and a p orbital from the same shell mix and overlap to create three orbitals of similar energy. The newly produced orbitals have s orbital properties of 33.33% and p orbital properties of 66.66%.
Polarity in nitromethane (CH3NO2)
Polarity is a concept that arises from the fact that electrical charge can be separated within a molecule, forming a positively charged end and a negatively charged end.
This is the case for nitromethane (CH3NO2) as it is considered one of the most polar solvents on earth. If we calculate the formal charge of nitromethane (CH3NO2) using the formula
Formal charge = the number of valence electrons in the free atom - [the number of lone pairs - half the number of bonding electrons]
The total fee is zero. It is important to realize that all atoms except nitrogen and oxygen have no formal charge. The nitrogen atom has a formal charge of +1 while oxygen has -1. Because they cancel, the net dipole moment is zero.
In contrast, the observed dipole moment of nitromethane (CH3NO2) is slightly larger, making it polar in nature. This anomaly appears due to the hyperconjugation effect, which leads to the delocalization of those electrons that participate in the formation of the bond with sigma (σ) properties.
Here it is important to know that a covalent single bond has only one sigma bond, a double bond has one sigma bond and one pi bond, while a triple bond has one sigma bond and two pi bonds.
When delocalization of electrons occurs in nitromethane, its structure changes where the double bond moves between the carbon atom and the nitrogen atom, which was previously between the nitrogen atom and the oxygen atom. Since we know that nitrogen has a positive charge and oxygen has a negative charge, changing the position of the double bond increases the positive charge on nitrogen.
Now the formal charges of nitrogen and oxygen do not cancel each other, so the net dipole moment persists and electrical charge separation occurs. For this reason, nitromethane (CH3NO2) is polar in nature.
The behavior of nitromethane (CH3NO2) can be studied in detail using its resonance structures. It is important to know that nitromethane and methyl nitrite are different molecules with similar molecular formulas.
Much can be studied about a molecule through the Lewis structure, where in this piece we explore molecular geometry, hybridization, and polarity. When a molecule can have many Lewis structures, choosing the one that offers maximum stability is crucial.
A double bond present in one leg is much more stable than that between the central atoms. The molecular geometry of nitromethane dictates that the molecule follows all ideal conditions, giving an idea that other molecular geometry parameters conform to ideal requirements. In addition, hybridization and polarity also correspond to the expected conditions.
CH3NO2 is a tetrahedral shape. It has two central atoms carbon and nitrogen. Out of them carbon is attached with four atoms and forms 4 sigma bonds and shows AX4 generic hybridization. Hence it has a tetrahedral shape.Is ch3no2 a polar or nonpolar molecule? ›
Nitromethane, sometimes shortened to simply "nitro", is an organic compound with the chemical formula CH3NO2. It is the simplest organic nitro compound. It is a polar liquid commonly used as a solvent in a variety of industrial applications such as in extractions, as a reaction medium, and as a cleaning solvent.What is the hybridization of ch3 nh2? ›
Answer. Both the carbon and the nitrogen atom in CH3NH2 are sp3-hybridized. The C-N sigma bond is an overlap between two sp3 orbitals.What is the hybridization of HNO2? ›
Hybridisation of N atom in HNO2 and HNO3 is sp^2 .Which hybridization is polar? ›
So Hybridisation is sp3. Since it is having unsymmetrical angular structure so it is polar.How many sigma bonds are in CH3NO2? ›
Indicate sigma (σ) and pi (Π) bonds in the molecule :CH3NO2 - India Site. There are three C–H sigma bonds, one C–N sigma bond, one N–O sigma bond, and one N=O. pi bond in the given compound.What polarity is nonpolar? ›
When things are different at each end, we call them polar. Some molecules have positive and negative ends too, and when they do, we call them polar. If they don't, we call them non-polar. Things that are polar can attract and repel each other (opposite charges attract, alike charges repel).What type of molecule is polar and nonpolar? ›
Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.Is CH3NH2 classified as polar or nonpolar? ›
As a result, methylamine (CH3NH2) is a polar molecule.Is CH3 example of sp2 hybridization? ›
Planar CH3 (methyl free radical) possesses a sp2 hybridization of the C atom, resulting in its planar structure. In addition, (methyl carbonium ion) is also planar (sp2). The lone pair of electrons is located in one of the hybrid orbitals of the (methyl carbanion) tetrahedral structure (sp3).
In CH3+ the one valency is still free, so the electrons taking part in bond forming are contained in 2s,2px,2py but 2pz don't have any electrons so it is not participating in bonding.So hybridization is sp2 as 2p orbitals and 1s orbital are taking part in hybridization.How do you determine hybridization? ›
An easy way to figure out what hybridization an atom has is to just count the number of atoms bonded to it and the number of lone pairs. Double and triple bonds still count as being only bonded to one atom.How does no2 have sp2 hybridization? ›
Nitrogen Dioxide (NO2) involves an sp2 hybridization type. The simple way to determine the hybridization of NO2 is by counting the bonds and lone electron pairs around the nitrogen atom and by drawing the Lewis structure. We will also find that in nitrogen dioxide, there are two sigma bonds and one lone electron pair.Is no2 sp2 hybridized? ›
Hybridization of NO2 (Nitrogen Dioxide)
|Name of the Molecule||Nitrogen Dioxide|
Polarity of Molecules
Polar Molecules: A polar molecule is usually formed when the one end of the molecule is said to possess more positive charges and whereas the opposite end of the molecule has negative charges, creating an electrical pole.
Nitrogen, oxygen, and chlorine atoms can also be sp3 hybridized in organic molecules. This means that nitrogen has three half-filled sp3 orbitals and can form three bonds which are pyramidal in shape. Oxygen has two half-filled sp3 orbitals and can form two bonds which are angled with respect to each other.What are the pi bonds in CH3NO2? ›
CH3NO2 has 6 sigma and 1 pi bond.How many sigma bonds are in OCN? ›
(a) There are two sigma and two pi bonds.How many σ bonds are present in CH3? ›
Acetonitrile CH3−C≡N contains 5 σ and 2 π bonds. There are three C-H σ bonds, one C-C σ sigma bond and on C-N σ bond.What is the use of CH3NO2? ›
Nitromethane is a colorless, oily liquid with a mild disagreeable or fruity odor. It is used as a propellant, fuel additive, rocket fuel, and solvent, and in making dyes, textiles, pharmaceuticals, and explosives.
Introduction. Nitromethane, CH3NO2, is the simplest alkyl species containing the nitro (−NO2) functional group.What is the dipole moment of CH3NO2? ›
The nitromethane molecule has a large dipole moment, 3.46 D,1 which is sufficient for for- mation of dipole bound anions.How do you determine if a Lewis structure is polar or nonpolar? ›
Molecules in which all of the atoms surrounding the central atom are the same tend to be nonpolar if there are no lone pairs on the central atom. If some of the atoms surrounding the central atom are different, however, the molecule may be polar.How can you tell the difference between polar and nonpolar molecules? ›
|Difference between Polar and Nonpolar|
|The molecules with polar bonds are usually asymmetrical.||The molecules with non polar bonds are usually symmetrical.|
|It has electrical poles.||It does not have electrical poles.|
Carbon dioxide is a linear molecule while sulfur dioxide is a bent molecule. Both molecules contain polar bonds (see bond dipoles on the Lewis structures below), but carbon dioxide is a nonpolar molecule while sulfur dioxide is a polar molecule.Which groups are polar and nonpolar? ›
An example of a nonpolar group is the methyl group (see discussion in Atoms to Bonds for more detail). Among the polar functional groups is the carboxyl group found in amino acids, some amino acid side chains, and the fatty acids that form triglycerides and phospholipids.Why is CH3NH2 polar? ›
Methyl amine ie CH3NH2 is a polar molecule. Polarity is the result of significant electronegativity difference between atoms.Does CH3NH2 contain polar bonds? ›
(b) CH3NH2 and CH3F are both covalent compounds and have polar bonds. The dipole in CH3NH2 can H-bond while that in CH3F cannot.Does CH3NH2 have dispersion? ›
Methylamine (CH3NH2), has London dispersion, dipole-dipole, and hydrogen bonding. Fluoromethane (CH3F), has London dispersion and dipole-dipole only. Therefore methylamine is predicted to have the higher boiling point since it has more (stronger) intermolecular forces than fluoromethane.What is the hybridization of CH3? ›
Therefore, the hybridization of C atom in CH3 radical will be sp2.
So, Shape & type of hybridization found in methylium (CH3+) ion are trigonal planar & sp2.Why is CH3 radical sp2? ›
1 Answers. In methyl free radical the hybridization is sp2 because it has 3 bond pairs and one unpaired electron which is very reactive so in hybridization it is not included and 3 bond pairs are present so one goes with s and other 2 with p.Is CH3 a trigonal planar? ›
4. Shapes: CH3 groups are tetrahedral, the other C atom is trigonal planar.Is CH3 a polar or nonpolar molecule? ›
When we take CH3 only, then we say that it is non-polar because the C and H have similar electronegativities. So, they cancel each other and thus CH3 is non-polar.What is an example of a sp2 hybridization? ›
Some examples of the sp2 hybridisation are as follows:
Linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral are the five basic shapes of hybridisation. The orbital arrangement's geometry is as follows: Octahedral: In octahedral geometry, six electrons are involved in making sp3d2 hybridisation.
In sp² hybridization, one s orbital and two p orbitals hybridize to form three sp² orbitals, each consisting of 33% s character and 67% p character. This type of hybridization is required whenever an atom is surrounded by three groups of electrons.How do you know if something has sp2 hybridization? ›
Ch 2: sp2 hybridisation. When a C atom is attached to 3 groups and so is involved in 3 σ bonds, it requires 3 orbitals in the hybrid set. This requires that it is sp2 hybridised.Is sp2 hybridization polar? ›
Molecules with sp2 hybridization have 120o bond angles. The structure of formaldehyde is shown below. It is a polar compound because of the electronegativity of oxygen and the molecular shape of formaldehyde.What bond shape is sp2 hybridization? ›
For sp2 hybridized central atoms the only possible molecular geometry is trigonal planar. If all the bonds are in place the shape is also trigonal planar.Which molecule has sp2 hybridized nitrogen? ›
Hybridization - Nitrogen, Oxygen, and Sulfur. The nitrogen atom also hybridizes in the sp2 arrangement, but differs from carbon in that there is a "lone pair" of electron left on the nitrogen that does not participate in the bonding. The geometry about nitrogen with three bonded ligands is therefore trigonal pyramidal.
The hybridization of atomic orbitals of nitrogen in NO+2, NO−3 and NH+4respectively are sp, sp2 and sp3. NO+2 is linear NO−3 is planar and NH+4 is tetrahedral.Does CO2 have sp2? ›
The atom of carbon in CO2 has 2 double bonds, one having each atom of oxygen. So, the hybridisation of carbon is sp. Every single oxygen atom in CO2 comes with a single double bond with the carbon. Moreover, each hydrogen's hybridisation is then sp2.Does CO2 have sp2 hybridization? ›
In the carbon dioxide molecule, oxygen also hybridizes its orbitals to produce three sp2 hybrid orbitals. The p orbital in the oxygen atom remains unchanged and is primarily used to form a pi bond. However, out of these three sp hybrid orbitals, only one will be used to produce a bond with the carbon atom.What is the hybrid structure of nitromethane? ›
Consider, for ex- ample, the structure of nitromethane, H3CLNO2. The double-headed arrow (SLLA) means that nitromethane is a single compound that is the “average” of both structures; nitromethane is said to be a resonance hybrid of these two structures.How to determine the hybridization of an atom in a Lewis structure? ›
An easy way to figure out what hybridization an atom has is to just count the number of atoms bonded to it and the number of lone pairs. Double and triple bonds still count as being only bonded to one atom.What are the structural isomers of ch3no2? ›
|Sr. No.||Nitro methane (Nitro-form)||Methyl nitrite (Aci-form)|
|(ii)||Dissolves in NaOH slowly.||Dissolves in NaOH instantly.|
The hybridization of methane molecules occurs by mixing one orbital with three p orbitals. Each orbital consists of one unpaired electron. The s and three p orbitals of carbon overlap with the 1s orbitals of hydrogen to form bonds. Thus methane is sp3 hybridized.Which type of hybridization is found in methane molecule *? ›
After completing this section, you should be able to describe the structure of methane in terms of the sp3 hybridization of the central carbon atom.What is the resonating structure of CH3NO2? ›
Answer and Explanation: The given molecule CH3NO2 C H 3 N O 2 has pi electrons and lone pairs placed nearby; due to this reason, nitromethane can show resonance. The resonance structures of nitromethane are as drawn below: The delocalization of electrons is observed in the nitro group attached to methane.What is the hybridization of CH3 ch2? ›
Answer: Carbon - sp2 hybridization: A carbon atom bound to three atoms (two single bonds, one double bond) is sp2 hybridized and forms a flat trigonal or triangular arrangement with 120° angles between bonds.
|No. of sigma bonds that carbon forms||Hybridisation state|