CH3NH3+ Lewis structure

CH₃NH₃⁺ has one carbon atom, six hydrogen atoms, and one nitrogen atom.

In CH₃NH₃⁺ Lewis structure, there is a single bond between the carbon and nitrogen atom. Both carbon and nitrogen atoms are attached with two hydrogen atoms, and none of the atoms has a lone pair.

Also, there is a positive (+1) charge on the nitrogen atom.

Alternative method: Lewis structure of CH₃NH₃⁺

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, carbon lies in group 14, hydrogen lies in group 1, and nitrogen lies in group 15.

Hence, carbon has four valence electrons, hydrogen has one valence electron, and nitrogen has five valence electrons.

Since CH₃NH₃⁺ has one carbon atom, six hydrogen atoms, and one nitrogen atom, so…

Valence electrons of one carbon atom = 4 × 1 = 4
Valence electrons of six hydrogen atoms = 1 × 6 = 6
Valence electrons of one nitrogen atom = 5 × 1 = 5

Now the CH₃NH₃⁺ has a positive (+1) charge, so we have to subtract one electron.

So the total valence electrons = 4 + 6 + 5 – 1 = 14

Learn how to find: Carbon valence electrons, Hydrogen valence electrons, and Nitrogen valence electrons

• Second, find the total electron pairs

We have a total of 14 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 14 ÷ 2 = 7

• Third, determine the central atom

Here hydrogen can not be the central atom. Because the central atom is bonded with at least two other atoms, and hydrogen has only one electron in its last shell, so it can not make more than one bond.

Now we have to choose the central atom from carbon and nitrogen. Place the least electronegative atom at the center.

Since carbon is less electronegative than nitrogen, assume that the central atom is carbon.

Therefore, place carbon in the center and hydrogen and nitrogen on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 7 electron pairs. And seven bonds are already marked. So we do not have to mark any electron pair as a lone pair on the sketch.

Formal charge

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For carbon atom, formal charge = 4 – 0 – ½ (8) = 0

For each hydrogen atom, formal charge = 1 – 0 – ½ (2) = 0

For nitrogen atom, formal charge = 5 – 0 – ½ (8) = +1

Here, the nitrogen atom has a charge, so mark it on the sketch as follows:

Final structure

The final structure of CH₃NH₃⁺ consists of a carbon atom linked to a nitrogen atom through a single covalent bond. In this arrangement, the carbon atom is bonded to three hydrogen atoms, while the nitrogen atom is bonded to three hydrogen atoms as well. Both the carbon and nitrogen atoms satisfy the octet rule by forming four bonds each, and every hydrogen atom reaches its stable duet state through its single shared electron pair. This configuration is the most stable because it results in a formal charge of zero on the carbon atom and +1 on the nitrogen atom, representing the most energetically favorable distribution for the ion. Consequently, this specific electronic distribution serves as the definitive and most accurate Lewis representation of the methylammonium ion.

To complete the representation, draw square brackets around the entire Lewis structure and place a “+” or “+1” sign as a superscript outside the upper right bracket. This notation signifies that the positive charge is a property of the whole ion.

Next: SeI₂ Lewis structure

External links

• https://www.chegg.com/homework-help/questions-and-answers/would-draw-lewis-structure-ch3nh3-m-sure-turn-h-h-q31188419
• https://oneclass.com/homework-help/chemistry/7052946-ch3nh3-lewis-structure.en.html