1. Determine the Lewis structure of isocyanic acid (HNCO):
* Carbon (C) is the central atom as it's the least electronegative.
* Nitrogen (N) and Oxygen (O) are more electronegative than carbon.
* Hydrogen (H) always forms one bond.
The Lewis structure of HNCO is:
```
H
|
N=C=O
```
2. Count the total valence electrons:
* H: 1 valence electron
* N: 5 valence electrons
* C: 4 valence electrons
* O: 6 valence electrons
Total valence electrons: 1 + 5 + 4 + 6 = 16
3. Determine the electron configuration of HNCO:
* The structure shows that carbon forms a triple bond with nitrogen, a double bond with oxygen, and a single bond with hydrogen.
* Carbon has 4 electrons involved in bonding (1 sigma and 3 pi bonds).
* Nitrogen has 4 electrons involved in bonding (1 sigma and 2 pi bonds).
* Oxygen has 4 electrons involved in bonding (1 sigma and 2 pi bonds).
* Hydrogen has 1 electron involved in bonding (1 sigma bond).
4. Assign the electrons to orbitals:
* Carbon: 2s² 2p²
* Nitrogen: 2s² 2p³
* Oxygen: 2s² 2p⁴
* Hydrogen: 1s¹
The total electron configuration for HNCO is:
(1s¹)(2s² 2p²)(2s² 2p³)(2s² 2p⁴) = 1s² 2s² 2p⁶
5. Identify the noble gas with this configuration:
* The noble gas with the electron configuration 1s² 2s² 2p⁶ is Neon (Ne).
Therefore, Neon (Ne) is the noble gas that has atoms in the ground state with the same electron configuration as isocyanic acid (HNCO).
