Is NH2- a polar or nonpolar substance?

The NH2- ion is referred to as Azanide by the IUPAC. In organic chemistry, this ion is also known as an Amino group. The ‘R’ stands for this amino group. Azanide (NH2-) is the conjugate base of Ammonia (NH3), meaning it is generated when Ammonia self-ionizes (NH3). In this essay, I’ll go through whether NH2- is polar or non-polar in depth.

Do you think NH2- is polar or nonpolar? Yes, NH2- is a polar substance. Nitrogen atoms are more electronegative than hydrogen atoms, resulting in an uneven charge distribution on nitrogen and hydrogen atoms, resulting in a net dipole moment and bent form. As a result, the NH2- (Amide ion) has a polar character.

Other names for NH2- include Amide ion, Amide, Ammonia ion, and Monoamide. In organic chemistry, an amide ion is not the same as an amide. The deprotonation of ammonia produces these. Ammonia acts as an acid in this process, albeit a weak acid. The generated amides are strong bases after deprotonation of ammonia.

Deprotonation of NH3 (Ammonia) H+ + NH2- (Amide ion)

In organic chemistry, however, Amides are generated by reacting Amines with Carboxylic acid. These are also useful in a variety of other reactions.

Polar molecules have two poles, just like a magnet, and each pole has two opposite charges.

Polarity is a chemical feature in which the separation of charges in a molecule results in the formation of two poles (positive and negative).

The unequal distribution of charges on the atoms is due to the differential in electronegativities of the Hydrogen and Nitrogen atoms. As a result, the NH2- molecule has a net dipole moment. As a result, the amide ion (NH2) is polar.

Shape of NH2 and bond angle

A single Nitrogen and two Hydrogen atoms make up the NH2- molecule. The Amide ion has a total of 8 valence electrons, two of which are linked as N-H bonds while the remaining two are lone pairs on the Nitrogen atom.

The VSEPR hypothesis is used in chemistry to predict the geometrical forms of molecules. It also asserts that every molecule takes its structure in such a way that the electrical repulsion between each atom’s valence electrons is reduced.

It’s also worth noting that repulsion between lone pairs is larger than repulsion between bond pairs and bond pairs.

Similarly, the two bonds formed between Hydrogen and Nitrogen are forced downward by the lone pairs present on the Nitrogen atom. Both bonds bend downward due to lone pair-lone pair repulsion and lone pair-bond pair repulsion, resulting in a bent V-shape (angular).

In the NH2- molecule, the bond angle between the two N-H bonds is roughly 104.5 degrees. The electrical repulsion strengthens the link between the two.

Hybridization of Nh2-

A formula can be used to calculate a molecule’s hybridization.

Hybridization formula = 1/2(V + M -C +A)

M is the number of monoatomic atoms that are coupled to the centre atom.

V = centre atom’s valence electron

Anionic charge (A)

cationic charge (C)

As we know, NH2- is an anion, hence the values are as follows:

V=5; M=2; C=0; A=1; V=5; M=2; C=0; A=1; V

1/2(5+2+1)= 4= sp3 hybridization of NH2-

As a result, NH2- hybridization is sp3.

Polarity is influenced by a variety of factors.

A molecule’s polarity is determined by a number of factors. All of them will be briefly discussed.

Dipole moment: A polar molecule’s net dipole moment is always positive. It is defined as a metric for calculating the polarity of a chemical bond between two atoms. In order to determine polarity, the electric dipole moment idea is used.

A vector quantity is the dipole moment. It has a definite magnitude as well as a specific direction.

The letter ‘D’ stands for it. The product of the charge and the distance between the charges is used to calculate the dipole moment. The dipole moment’s direction is measured from negative to positive.

The net dipole moment in a chemical molecule can also be zero if the net dipole moments of the bonds between atoms cancel each other out. Even though the dipole moment of the C-O bond is 0.122 D, CO2 (Carbon dioxide) has zero net dipole moment.

D = q * r = D = q * r = D = q *

D is the dipole moment.

q stands for charge.

r stands for the distance between the charges.

Electronegativity: Another significant aspect that defines a molecule’s polarity is its electronegativity. When there is a difference between the electronegativities of two atoms in a molecule, the bond between them is polar.

The polarity of a link between two atoms is proportional to the difference between their electronegativities.

The electronegativities of the Nitrogen and Oxygen atoms differ in the Amide ion, causing the N-H bond to be polar.

Nitrogen has an electronegativity of 3.04, while oxygen has an electronegativity of 2.2. The N-H bond becomes polar as a result of this divergence.

For example, an oxygen molecule is made up of two oxygen atoms with the same electronegativity, resulting in a charge distribution on the oxygen atoms that is equal. As a result, the molecule of oxygen is non-polar.

Symmetry is also an important aspect in defining a molecule’s polarity. The geometrical structure of a molecule can be used to determine polarity.

The dipole moment of a symmetrical molecule is 0, indicating that the molecule is non-polar.

Unsymmetrical molecules, on the other hand, have a net dipole moment, making them polar molecules.

It is unsymmetrical, as in the case of Amide ion (NH2-), making it a polar molecule.

To determine whether a molecule is polar or non-polar, the characteristics listed above are sufficient.

You must also refer to NH2 lewis structure, geometry, and hybridization when discussing lewis structure and geometry.

The NH2- ion’s properties

Amide ion has a molecular mass of roughly 16.024 gmol1.

It is Ammonia’s conjugate base (NH3), which is an exceptionally powerful base capable of gaining an extra proton to make ammonia.

The NH2- molecule has eight valence electrons.

It is also known as Nitrogen Hydride and is a monovalent ion.

Read more: Is SeF4 a polar or non-polar substance?

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.


Please enter your comment!
Please enter your name here

Read More