NH2OH lewis structure, molecular geometry, and its bond angle
Hydroxylamine appears as vivid white, opaque crystals and has a chemical formula NH2OH or H3NO. It is used as an aqueous solution and an intermediate in biological nitrification.
In this article, we will discuss H3NO or NH2OH lewis structure, molecular geometry, and its bond angle, etc.
Hydroxylamine is an unstable, odorless, and hygroscopic compound. It is commonly used as a nucleophilic reagent, reducing agents in organic and inorganic reactions.
In the NH2OH lewis structure, there are two N-H bonds, one N-O bond, and one O-H bond.
The hydrogen atoms are situated in the terminal position.
A total of 4 bond pairs and 3 lone pairs are present in the lewis structure of NH2OH.
Follow some steps for drawing the lewis dot structure for NH2OH
1. Count total valence electrons in NH2OH
Valence electrons are found in the outer shell of the atom that can form a chemical bond with another atom. To find the valence electron in NH2OH, look at the group number of individual atoms – nitrogen, hydrogen, and oxygen.
The nitrogen atom belongs to the pnictogens family and has a group number 15, hence, its valence electron is 5, the oxygen atom is situated in group number 16, hence, its valence electron is 6.
The hydrogen atom is situated in the first row of the Periodic Table and has period group number 1, hence, its valence electron is 1.
∴ Total number of valence electrons available for the NH2OH Lewis structure = 5 + 1(3) + 6 = 14 valence electrons [∴ NH2OH molecule has 1 nitrogen, 3 hydrogen and 1 oxygen atom]
2. Find the least electronegative atom and place it at center
The best preferable element for the central position is the least electronegative atom in the molecule. But it should be noted that the hydrogen atom always goes outside in the lewis diagram because it can only make a maximum of one bond.
So, in the case of NH2OH, the hydrogen goes outside in the lewis diagram, and among nitrogen and oxygen, look at their electronegativity value.
The electronegativity of nitrogen is 3.04 and for oxygen, it is 3.44. Clearly, the nitrogen atom is less electronegative, hence, put the nitrogen atom in the central position and other atoms as shown in the figure given below.
The nitrogen is in center, the two hydrogen either side of it and one hydrogen should attached to the oxygen atom, this will make OH group.
3. Connect outer atoms to central atom with a single bond
Draw the skeletal structure of NH2OH as shown below.
Look at the above structure and determine the number of valence electrons is used till now.
In the above structure, four single bonds are used and every single bond contains 2 electrons, hence, (4 × 2) = 8 valence electrons are used from 14 total available valence electrons for drawing the lewis structure of NH2OH.
∴ (14 – 8) = 6 valence electrons
So, we are left with 6 valence electrons more.
4. Complete the octet of the atoms
In this step, we have to complete the octet of all atoms starting from the outer atom first.
Now, in the case of NH2OH, hydrogen is the outer atom and it needs only 2 electrons to fulfill the octet since it has only 1s shell which can be filled maximum of 2 electrons.
The hydrogen atoms already completed their octet since they have 2 electrons(one single bond) in their valence shell.
Now, the oxygen and nitrogen both need 8-8 electrons in their valence shell to complete the octet. Looking at the 3rd step structure of NH2OH, we see that the nitrogen atom is attached to the three bond pairs means 6 electrons.
Hence, the nitrogen already has 6 electrons in its valence shells means it needs only two more. An oxygen atom is attached to the two-bond pair which means, it has 4 electrons in its valence shell, therefore, it needs 4 more electrons to complete the octet.
So, the nitrogen atom needs 2 electrons and the oxygen atom needs 4 electrons to complete their octet. And we have already 6 remaining valence electrons.
Therefore, put these remaining valence electrons over oxygen and nitrogen and complete their octet shell.
That’s all, all the atoms in the above NH2OH lewis structure fulfilled their octet and attains stability and we also used all the total valence electrons that are available for drawing it.
Now we will check the above structure stability by evaluating the formal charge for each atom.
5. Check the stability with the help of a formal charge concept
To calculate the formal charge on an atom. Use the formula given below-
The nonbonding electrons are basically lone pair electrons and bonding electrons are shared electrons that are found in between the atoms.
Let’s calculate the formal charge for nitrogen, oxygen, and hydrogen atoms in the NH2OH lewis structure.
For nitrogen atom:
Valence electrons of nitrogen = 5
Nonbonding electrons on nitrogen= 2
Bonding electrons around nitrogen(3 single bond) = 6
∴ (5 – 2 – 6/2) = 0 formal charge on nitrogen central atom.
For hydrogen atom
Valence electrons of hydrogen = 1
Nonbonding electrons on hydrogen = 0
Bonding electrons around hydrogen (1 single bond) = 2
∴ (1 – 0 – 2/2) = 0 formal charge on the hydrogen atom.
For oxygen atom
Valence electrons of oxygen = 6
Nonbonding electrons on oxygen =4
Bonding electrons around oxygen (2 single bonds) = 4
∴ (6 – 4 – 4/2) = 0 formal charge on the oxygen atom.
So, all-atom in the above structure gets a formal charge equal to zero, hence, this is our most stable and appropriate lewis structure of NH2OH or H3NO.
What is the bond angle and molecular geometry of NH2OH?
The molecular geometry of NH2OH is Trigonal pyramidal and its electron geometry is tetrahedral since the central atom nitrogen has 4 electrons pairs around it(3 bond pair + 1 lone pair) which makes it an AX3N type molecule.
The bond angle of NH2OH is followed as ∠H-N-H = 107º, ∠H-N-O = 103.3º, and ∠N-O-H = 101.4º.
How many valence electrons are available for lewis’s structure of NH2OH?
⇒ Total number of the valence electron in Nitrogen = 5
⇒ Total number of the valence electrons in hydrogen = 1
⇒ Total number of the valence electrons in oxygen = 6
∴ Total number of valence electrons available for the NH2OH Lewis structure = 5 + 1(3) + 6 = 14 valence electrons [∴ NH2OH molecule has 1 nitrogen, 3 hydrogen and 1 oxygen atom]
How many bond pairs and lone pairs are present in the lewis structure of NH2OH?
Bonding pairs are the pair of electrons that are in a bond. A single bond has one bond pair means 2 bonding electrons.
Lone pairs are those represented as dots in the lewis diagram that do not take part in the formation of bonds and are also called nonbonding electrons.
So, in the NH2OH lewis structure, there are 4 bond pairs means 8 bonding electrons and 3 lone pairs (1 on the central atom + 2 on the oxygen atom) are present.
Why the electron geometry of NH2OH is tetrahedral?
The electron geometry considers both bond pair and lone pair while predicting the geometry of the molecule. And molecular geometry only considers the bond pair to predict the shape of the molecule.
So, as per the NH2OH lewis structure, the nitrogen central atom is surrounded by 4 electron pairs(3 bond pairs + 1 lone pair).
∴ Four regions of electron density always form a tetrahedral geometry, hence, the electron geometry of NH2OH is tetrahedral.
Vishal Goyal is the founder of Topblogtenz, a comprehensive resource for students seeking guidance and support in their chemistry studies. He holds a degree in B.Tech (Chemical Engineering) and has four years of experience as a chemistry tutor. The team at Topblogtenz includes experts like experienced researchers, professors, and educators, with the goal of making complex subjects like chemistry accessible and understandable for all. A passion for sharing knowledge and a love for chemistry and science drives the team behind the website. Let's connect through LinkedIn: https://www.linkedin.com/in/vishal-goyal-2926a122b/
Topblogtenz is a website dedicated to providing informative and engaging content related to the field of chemistry and science. We aim to make complex subjects, like chemistry, approachable and enjoyable for everyone.
