Q. What is the molecular geometry of \(\mathrm{CO_2}\)?

\( \textbf{Goal:} \) Determine the molecular geometry of carbon dioxide, \( \text{CO}_2 \).

\( \textbf{Step 1: Identify the Lewis structure and the central atom} \)

\( \text{CO}_2 \) has the structure \( \text{O}=\text{C}=\text{O} \). The central (least electronegative) atom is carbon.

\( \textbf{Step 2: Count electron-domain regions around the central atom} \)

Geometry is determined by the number of electron domains (regions of electron density) around the central atom using VSEPR theory.

In \( \text{O}=\text{C}=\text{O} \), carbon has two bonding pairs:

\( \cdot \) one double bond to the left oxygen

\( \cdot \) one double bond to the right oxygen

Each double bond counts as one electron domain for VSEPR. So the total number of electron domains around carbon is

\[ \text{Number of electron domains} = 2 \]

\( \textbf{Step 3: Determine the electron-domain geometry} \)

For \(2\) electron domains, the electron-domain geometry is linear.

\( \textbf{Step 4: Check for lone pairs on the central atom} \)

Carbon in \( \text{CO}_2 \) has no lone pairs in the Lewis structure. Therefore, there are no extra electron domains that would bend the molecule.

\( \textbf{Step 5: Name the molecular geometry} \)

With \(2\) electron domains and \(0\) lone pairs on the central atom, the molecular geometry is also linear.

\( \textbf{Final Answer:} \) The molecular geometry of \( \text{CO}_2 \) is \(\textbf{linear}\), with an ideal bond angle of \(180^\circ\).