Lewis Structures: Draw the Lewis Structure for methylamine Part A Draw the Lewis structure of CH
NH
, a neutral compound. Draw the Lewis dot structure of CH
NH
.
The Correct Answer and Explanation is:
To draw the Lewis structure of methylamine (CH₃NH₂), we follow a systematic approach to represent all valence electrons and bonds correctly:
Lewis Structure of CH₃NH₂
H H
\ /
H — C — N — H
|
H
Each line represents a bonding pair of electrons, and lone pairs on nitrogen are not shown here but should be drawn as one pair of non-bonding electrons on the nitrogen atom.
Step-by-Step Explanation
Methylamine consists of one carbon (C), five hydrogen (H), and one nitrogen (N) atom. The total number of valence electrons is calculated by summing the contributions from each atom:
- Carbon contributes 4 valence electrons
- Nitrogen contributes 5 valence electrons
- Each hydrogen contributes 1 valence electron × 5 = 5
Total valence electrons = 4 + 5 + 5 = 14 electrons
We aim to place atoms so that hydrogen forms one bond, carbon forms four bonds, and nitrogen forms three bonds plus one lone pair. Carbon typically forms a tetrahedral geometry, while nitrogen in amines adopts a pyramidal geometry.
Begin by connecting carbon to three hydrogens and one nitrogen. Then, attach two hydrogens to nitrogen. This arrangement uses all five hydrogens and provides a stable bonding framework. At this point, nitrogen has three single bonds and retains one lone pair to satisfy the octet rule. Carbon also achieves an octet with four single bonds.
This structure reflects correct electron placement and bonding preferences for each element. It also highlights the polar nature of methylamine, with the nitrogen end slightly more negative due to its lone pair and higher electronegativity.
Overall, this Lewis structure not only satisfies valence requirements but also aligns with molecular geometry and polarity considerations found in real molecules like methylamine.
