For the H 3 CNCO molecule, (Note: The atoms are bonded in the order CNCO, with the three H atoms bonded to the first carbon atom.) answer the following questions.
What is the ideal H-C-H bond angle?
(0, 30, 45, 60, 90, 109, 120, 145, or 180.)
What is the ideal N-C-O bond angle?
(0, 30, 45, 60, 90, 109, 120, 145, or 180.)
What is the ideal C-N-C bond angle?
(0, 30, 45, 60, 90, 109, 120, 145, or 180.)
To determine the ideal bond angles for the H3CNCO molecule, we need to consider its molecular geometry.
The molecular geometry of a molecule is determined by the arrangement of its atoms and lone pairs. In the case of H3CNCO, we have four atoms bonded to the central carbon atom (C), along with three hydrogen (H) atoms bonded to the first carbon atom.
Let's analyze the molecular geometry step-by-step:
1. Start by drawing the Lewis structure for H3CNCO. The central C atom is bonded to an H atom and the N atom, which in turn is bonded to the second C atom and the O atom.
H H
│ │
H ─ C ─ N ─ C ─ O
│ │
H │
Note: The dashes represent bonds and the lines represent non-bonding electron pairs.
2. Now, label the positions around the central C atom with numbers:
H H
│ │
3 ─ C ─ N ─ C ─ O
│ │
H │
1 2
3. Looking at the Lewis structure, you can see that the H atoms are bonded to the first C atom. This means that the ideal H-C-H bond angle will determine the ideal bond angle between the H atoms and the first C atom.
4. The ideal bond angle for a molecule with a tetrahedral electron pair geometry, like H3CNCO, is approximately 109.5 degrees. Therefore, the ideal H-C-H bond angle in H3CNCO will also be around 109.5 degrees.
5. Moving on to the N-C-O bond angle, we need to consider the positions of the atoms. The N atom is bonded to the second C atom and the O atom.
6. Since the second C atom is the central atom for the N-C-O bond angle, we can again consider the ideal bond angle for a tetrahedral electron pair geometry, which is approximately 109.5 degrees.
7. Finally, let's determine the C-N-C bond angle. The central C atom is bonded to the N atom and the first C atom.
8. In this case, the central C atom reaches a trigonal planar electron pair geometry. The ideal bond angle for a trigonal planar geometry is 120 degrees. Therefore, the ideal C-N-C bond angle in H3CNCO will be 120 degrees.
To summarize:
- The ideal H-C-H bond angle is approximately 109.5 degrees.
- The ideal N-C-O bond angle is approximately 109.5 degrees.
- The ideal C-N-C bond angle is 120 degrees.