Question

check the box next to each molecule on the right that has the shape of the model molecule on the left: model molecules (check all that apply) c₂h₂ scn⁻ n₂h₂ h₂o none of the above note for advanced students: the length of bonds and size of atoms in the model is not necessarily realistic. the model is only meant to show general geometry and 3d shape of the molecule. you can drag the slider to rotate the molecule.

Explanation:

Step1: Identify linear - shaped molecules

Linear - shaped molecules have a bond angle of 180 degrees.

Step2: Analyze each molecule

• $\text{C}_2\text{H}_2$ (acetylene) has a triple - bond between the two carbon atoms and is linear with a bond angle of 180 degrees.
• $\text{SCN}^-$ has a linear structure with the central carbon atom double - bonded to sulfur and nitrogen, and a bond angle of 180 degrees.
• $\text{N}_2\text{H}_2$ has a bent structure around each nitrogen atom due to the presence of lone pairs and is not linear.
• $\text{H}_2\text{O}$ has a bent shape due to the two lone pairs on the oxygen atom and is not linear.

Answer:

$\text{C}_2\text{H}_2$, $\text{SCN}^-$